Mi duda está, en dónde voy al pulsar "examinar":
He intentado poner el nombre como me dijísteis y me dice que: "Orden no puede estar vacío".
Ahh eso, bueno, puedes probar solo escribiendo "thunderbird" o puedes buscarlo desde los archivos ejecutables para los grupos de usuarios estandar, ya que thunderbird es una aplicacion que no tiene parametros especiales, no es considerado su uso para root.
Ummm no estoy seguro si en ubuntu sea asi, pero en su hermanito gemelo Linux Mint la ruta de los ejecutables esta en la carpeta raiz del sistema de archivos "/usr/bin" ahi encontraras muchos programas que se ejecutan, o puedes buscar tambien en la carpeta en donde se haya instalado, y pues eso es como complicado de ubicar la verdad, pues las librerias y accesos linkeados referencias a muchas carpetas.
si tienes interés en buscar todo lo relacionado con thunderbird (o sobre cualquier archivo en particular) dentro de tu sistema, pues puedes usar el comando find de esta manera:
donde "/" es la raiz o sistema de archivos, donde esta todo lo de linux,
todoMira esto fue como me salio a mi:
find: `/proc/1741/map_files': Permission denied
find: `/proc/1741/fdinfo': Permission denied
find: `/proc/1741/ns': Permission denied
find: `/proc/1757/task/1757/fd': Permission denied
find: `/proc/1757/task/1757/fdinfo': Permission denied
find: `/proc/1757/task/1757/ns': Permission denied
find: `/proc/1757/fd': Permission denied
find: `/proc/1757/map_files': Permission denied
find: `/proc/1757/fdinfo': Permission denied
find: `/proc/1757/ns': Permission denied
find: `/proc/1776/task/1776/fd': Permission denied
find: `/proc/1776/task/1776/fdinfo': Permission denied
find: `/proc/1776/task/1776/ns': Permission denied
find: `/proc/1776/fd': Permission denied
find: `/proc/1776/map_files': Permission denied
find: `/proc/1776/fdinfo': Permission denied
find: `/proc/1776/ns': Permission denied
find: `/proc/1778/task/1778/fd': Permission denied
find: `/proc/1778/task/1778/fdinfo': Permission denied
find: `/proc/1778/task/1778/ns': Permission denied
find: `/proc/1778/fd': Permission denied
find: `/proc/1778/map_files': Permission denied
find: `/proc/1778/fdinfo': Permission denied
find: `/proc/1778/ns': Permission denied
find: `/proc/1810/task/1810/fd': Permission denied
find: `/proc/1810/task/1810/fdinfo': Permission denied
find: `/proc/1810/task/1810/ns': Permission denied
find: `/proc/1810/fd': Permission denied
find: `/proc/1810/map_files': Permission denied
find: `/proc/1810/fdinfo': Permission denied
find: `/proc/1810/ns': Permission denied
find: `/proc/1936/task/1936/fd': Permission denied
find: `/proc/1936/task/1936/fdinfo': Permission denied
find: `/proc/1936/task/1936/ns': Permission denied
find: `/proc/1936/task/1942/fd': Permission denied
find: `/proc/1936/task/1942/fdinfo': Permission denied
find: `/proc/1936/task/1942/ns': Permission denied
find: `/proc/1936/task/1943/fd': Permission denied
find: `/proc/1936/task/1943/fdinfo': Permission denied
find: `/proc/1936/task/1943/ns': Permission denied
find: `/proc/1936/task/1944/fd': Permission denied
find: `/proc/1936/task/1944/fdinfo': Permission denied
find: `/proc/1936/task/1944/ns': Permission denied
find: `/proc/1936/task/1945/fd': Permission denied
find: `/proc/1936/task/1945/fdinfo': Permission denied
find: `/proc/1936/task/1945/ns': Permission denied
find: `/proc/1936/task/1946/fd': Permission denied
find: `/proc/1936/task/1946/fdinfo': Permission denied
find: `/proc/1936/task/1946/ns': Permission denied
find: `/proc/1936/task/1947/fd': Permission denied
find: `/proc/1936/task/1947/fdinfo': Permission denied
find: `/proc/1936/task/1947/ns': Permission denied
find: `/proc/1936/task/1948/fd': Permission denied
find: `/proc/1936/task/1948/fdinfo': Permission denied
find: `/proc/1936/task/1948/ns': Permission denied
find: `/proc/1936/task/1949/fd': Permission denied
find: `/proc/1936/task/1949/fdinfo': Permission denied
find: `/proc/1936/task/1949/ns': Permission denied
find: `/proc/1936/task/1950/fd': Permission denied
find: `/proc/1936/task/1950/fdinfo': Permission denied
find: `/proc/1936/task/1950/ns': Permission denied
find: `/proc/1936/task/1951/fd': Permission denied
find: `/proc/1936/task/1951/fdinfo': Permission denied
find: `/proc/1936/task/1951/ns': Permission denied
find: `/proc/1936/task/1952/fd': Permission denied
find: `/proc/1936/task/1952/fdinfo': Permission denied
find: `/proc/1936/task/1952/ns': Permission denied
find: `/proc/1936/task/1953/fd': Permission denied
find: `/proc/1936/task/1953/fdinfo': Permission denied
find: `/proc/1936/task/1953/ns': Permission denied
find: `/proc/1936/task/1954/fd': Permission denied
find: `/proc/1936/task/1954/fdinfo': Permission denied
find: `/proc/1936/task/1954/ns': Permission denied
find: `/proc/1936/task/1955/fd': Permission denied
find: `/proc/1936/task/1955/fdinfo': Permission denied
find: `/proc/1936/task/1955/ns': Permission denied
find: `/proc/1936/task/1956/fd': Permission denied
find: `/proc/1936/task/1956/fdinfo': Permission denied
find: `/proc/1936/task/1956/ns': Permission denied
find: `/proc/1936/task/1957/fd': Permission denied
find: `/proc/1936/task/1957/fdinfo': Permission denied
find: `/proc/1936/task/1957/ns': Permission denied
find: `/proc/1936/task/1958/fd': Permission denied
find: `/proc/1936/task/1958/fdinfo': Permission denied
find: `/proc/1936/task/1958/ns': Permission denied
find: `/proc/1936/task/1959/fd': Permission denied
find: `/proc/1936/task/1959/fdinfo': Permission denied
find: `/proc/1936/task/1959/ns': Permission denied
find: `/proc/1936/task/1960/fd': Permission denied
find: `/proc/1936/task/1960/fdinfo': Permission denied
find: `/proc/1936/task/1960/ns': Permission denied
find: `/proc/1936/task/1961/fd': Permission denied
find: `/proc/1936/task/1961/fdinfo': Permission denied
find: `/proc/1936/task/1961/ns': Permission denied
find: `/proc/1936/task/1962/fd': Permission denied
find: `/proc/1936/task/1962/fdinfo': Permission denied
find: `/proc/1936/task/1962/ns': Permission denied
find: `/proc/1936/task/1963/fd': Permission denied
find: `/proc/1936/task/1963/fdinfo': Permission denied
find: `/proc/1936/task/1963/ns': Permission denied
find: `/proc/1936/task/1964/fd': Permission denied
find: `/proc/1936/task/1964/fdinfo': Permission denied
find: `/proc/1936/task/1964/ns': Permission denied
find: `/proc/1936/task/1965/fd': Permission denied
find: `/proc/1936/task/1965/fdinfo': Permission denied
find: `/proc/1936/task/1965/ns': Permission denied
find: `/proc/1936/task/1966/fd': Permission denied
find: `/proc/1936/task/1966/fdinfo': Permission denied
find: `/proc/1936/task/1966/ns': Permission denied
find: `/proc/1936/task/1967/fd': Permission denied
find: `/proc/1936/task/1967/fdinfo': Permission denied
find: `/proc/1936/task/1967/ns': Permission denied
find: `/proc/1936/task/1968/fd': Permission denied
find: `/proc/1936/task/1968/fdinfo': Permission denied
find: `/proc/1936/task/1968/ns': Permission denied
find: `/proc/1936/task/1969/fd': Permission denied
find: `/proc/1936/task/1969/fdinfo': Permission denied
find: `/proc/1936/task/1969/ns': Permission denied
find: `/proc/1936/task/1970/fd': Permission denied
find: `/proc/1936/task/1970/fdinfo': Permission denied
find: `/proc/1936/task/1970/ns': Permission denied
find: `/proc/1936/task/1971/fd': Permission denied
find: `/proc/1936/task/1971/fdinfo': Permission denied
find: `/proc/1936/task/1971/ns': Permission denied
find: `/proc/1936/task/1972/fd': Permission denied
find: `/proc/1936/task/1972/fdinfo': Permission denied
find: `/proc/1936/task/1972/ns': Permission denied
find: `/proc/1936/task/1973/fd': Permission denied
find: `/proc/1936/task/1973/fdinfo': Permission denied
find: `/proc/1936/task/1973/ns': Permission denied
find: `/proc/1936/task/1974/fd': Permission denied
find: `/proc/1936/task/1974/fdinfo': Permission denied
find: `/proc/1936/task/1974/ns': Permission denied
find: `/proc/1936/task/1975/fd': Permission denied
find: `/proc/1936/task/1975/fdinfo': Permission denied
find: `/proc/1936/task/1975/ns': Permission denied
find: `/proc/1936/task/1976/fd': Permission denied
find: `/proc/1936/task/1976/fdinfo': Permission denied
find: `/proc/1936/task/1976/ns': Permission denied
find: `/proc/1936/task/1977/fd': Permission denied
find: `/proc/1936/task/1977/fdinfo': Permission denied
find: `/proc/1936/task/1977/ns': Permission denied
find: `/proc/1936/task/1978/fd': Permission denied
find: `/proc/1936/task/1978/fdinfo': Permission denied
find: `/proc/1936/task/1978/ns': Permission denied
find: `/proc/1936/task/1979/fd': Permission denied
find: `/proc/1936/task/1979/fdinfo': Permission denied
find: `/proc/1936/task/1979/ns': Permission denied
find: `/proc/1936/task/1980/fd': Permission denied
find: `/proc/1936/task/1980/fdinfo': Permission denied
find: `/proc/1936/task/1980/ns': Permission denied
find: `/proc/1936/task/1981/fd': Permission denied
find: `/proc/1936/task/1981/fdinfo': Permission denied
find: `/proc/1936/task/1981/ns': Permission denied
find: `/proc/1936/task/1982/fd': Permission denied
find: `/proc/1936/task/1982/fdinfo': Permission denied
find: `/proc/1936/task/1982/ns': Permission denied
find: `/proc/1936/task/1983/fd': Permission denied
find: `/proc/1936/task/1983/fdinfo': Permission denied
find: `/proc/1936/task/1983/ns': Permission denied
find: `/proc/1936/task/1984/fd': Permission denied
find: `/proc/1936/task/1984/fdinfo': Permission denied
find: `/proc/1936/task/1984/ns': Permission denied
find: `/proc/1936/task/1985/fd': Permission denied
find: `/proc/1936/task/1985/fdinfo': Permission denied
find: `/proc/1936/task/1985/ns': Permission denied
find: `/proc/1936/task/1986/fd': Permission denied
find: `/proc/1936/task/1986/fdinfo': Permission denied
find: `/proc/1936/task/1986/ns': Permission denied
find: `/proc/1936/task/1987/fd': Permission denied
find: `/proc/1936/task/1987/fdinfo': Permission denied
find: `/proc/1936/task/1987/ns': Permission denied
find: `/proc/1936/task/1988/fd': Permission denied
find: `/proc/1936/task/1988/fdinfo': Permission denied
find: `/proc/1936/task/1988/ns': Permission denied
find: `/proc/1936/task/1989/fd': Permission denied
find: `/proc/1936/task/1989/fdinfo': Permission denied
find: `/proc/1936/task/1989/ns': Permission denied
find: `/proc/1936/task/1990/fd': Permission denied
find: `/proc/1936/task/1990/fdinfo': Permission denied
find: `/proc/1936/task/1990/ns': Permission denied
find: `/proc/1936/task/1991/fd': Permission denied
find: `/proc/1936/task/1991/fdinfo': Permission denied
find: `/proc/1936/task/1991/ns': Permission denied
find: `/proc/1936/task/1992/fd': Permission denied
find: `/proc/1936/task/1992/fdinfo': Permission denied
find: `/proc/1936/task/1992/ns': Permission denied
find: `/proc/1936/task/1993/fd': Permission denied
find: `/proc/1936/task/1993/fdinfo': Permission denied
find: `/proc/1936/task/1993/ns': Permission denied
find: `/proc/1936/task/1994/fd': Permission denied
find: `/proc/1936/task/1994/fdinfo': Permission denied
find: `/proc/1936/task/1994/ns': Permission denied
find: `/proc/1936/task/1995/fd': Permission denied
find: `/proc/1936/task/1995/fdinfo': Permission denied
find: `/proc/1936/task/1995/ns': Permission denied
find: `/proc/1936/task/1996/fd': Permission denied
find: `/proc/1936/task/1996/fdinfo': Permission denied
find: `/proc/1936/task/1996/ns': Permission denied
find: `/proc/1936/task/1997/fd': Permission denied
find: `/proc/1936/task/1997/fdinfo': Permission denied
find: `/proc/1936/task/1997/ns': Permission denied
find: `/proc/1936/task/1998/fd': Permission denied
find: `/proc/1936/task/1998/fdinfo': Permission denied
find: `/proc/1936/task/1998/ns': Permission denied
find: `/proc/1936/task/1999/fd': Permission denied
find: `/proc/1936/task/1999/fdinfo': Permission denied
find: `/proc/1936/task/1999/ns': Permission denied
find: `/proc/1936/task/2000/fd': Permission denied
find: `/proc/1936/task/2000/fdinfo': Permission denied
find: `/proc/1936/task/2000/ns': Permission denied
find: `/proc/1936/task/2001/fd': Permission denied
find: `/proc/1936/task/2001/fdinfo': Permission denied
find: `/proc/1936/task/2001/ns': Permission denied
find: `/proc/1936/task/2002/fd': Permission denied
find: `/proc/1936/task/2002/fdinfo': Permission denied
find: `/proc/1936/task/2002/ns': Permission denied
find: `/proc/1936/task/2003/fd': Permission denied
find: `/proc/1936/task/2003/fdinfo': Permission denied
find: `/proc/1936/task/2003/ns': Permission denied
find: `/proc/1936/task/2005/fd': Permission denied
find: `/proc/1936/task/2005/fdinfo': Permission denied
find: `/proc/1936/task/2005/ns': Permission denied
find: `/proc/1936/task/2006/fd': Permission denied
find: `/proc/1936/task/2006/fdinfo': Permission denied
find: `/proc/1936/task/2006/ns': Permission denied
find: `/proc/1936/fd': Permission denied
find: `/proc/1936/map_files': Permission denied
find: `/proc/1936/fdinfo': Permission denied
find: `/proc/1936/ns': Permission denied
find: `/proc/2020/task/2020/fd': Permission denied
find: `/proc/2020/task/2020/fdinfo': Permission denied
find: `/proc/2020/task/2020/ns': Permission denied
find: `/proc/2020/fd': Permission denied
find: `/proc/2020/map_files': Permission denied
find: `/proc/2020/fdinfo': Permission denied
find: `/proc/2020/ns': Permission denied
find: `/proc/2111/task/2111/fd': Permission denied
find: `/proc/2111/task/2111/fdinfo': Permission denied
find: `/proc/2111/task/2111/ns': Permission denied
find: `/proc/2111/fd': Permission denied
find: `/proc/2111/map_files': Permission denied
find: `/proc/2111/fdinfo': Permission denied
find: `/proc/2111/ns': Permission denied
find: `/proc/2167/task/2167/fd': Permission denied
find: `/proc/2167/task/2167/fdinfo': Permission denied
find: `/proc/2167/task/2167/ns': Permission denied
find: `/proc/2167/task/2169/fd': Permission denied
find: `/proc/2167/task/2169/fdinfo': Permission denied
find: `/proc/2167/task/2169/ns': Permission denied
find: `/proc/2167/task/2170/fd': Permission denied
find: `/proc/2167/task/2170/fdinfo': Permission denied
find: `/proc/2167/task/2170/ns': Permission denied
find: `/proc/2167/fd': Permission denied
find: `/proc/2167/map_files': Permission denied
find: `/proc/2167/fdinfo': Permission denied
find: `/proc/2167/ns': Permission denied
find: `/proc/2182/task/2182/fd': Permission denied
find: `/proc/2182/task/2182/fdinfo': Permission denied
find: `/proc/2182/task/2182/ns': Permission denied
find: `/proc/2182/task/2184/fd': Permission denied
find: `/proc/2182/task/2184/fdinfo': Permission denied
find: `/proc/2182/task/2184/ns': Permission denied
find: `/proc/2182/task/2186/fd': Permission denied
find: `/proc/2182/task/2186/fdinfo': Permission denied
find: `/proc/2182/task/2186/ns': Permission denied
find: `/proc/2182/task/2188/fd': Permission denied
find: `/proc/2182/task/2188/fdinfo': Permission denied
find: `/proc/2182/task/2188/ns': Permission denied
find: `/proc/2182/fd': Permission denied
find: `/proc/2182/map_files': Permission denied
find: `/proc/2182/fdinfo': Permission denied
find: `/proc/2182/ns': Permission denied
find: `/proc/2268/task/2268/fd': Permission denied
find: `/proc/2268/task/2268/fdinfo': Permission denied
find: `/proc/2268/task/2268/ns': Permission denied
find: `/proc/2268/task/2271/fd': Permission denied
find: `/proc/2268/task/2271/fdinfo': Permission denied
find: `/proc/2268/task/2271/ns': Permission denied
find: `/proc/2268/task/2274/fd': Permission denied
find: `/proc/2268/task/2274/fdinfo': Permission denied
find: `/proc/2268/task/2274/ns': Permission denied
find: `/proc/2268/fd': Permission denied
find: `/proc/2268/map_files': Permission denied
find: `/proc/2268/fdinfo': Permission denied
find: `/proc/2268/ns': Permission denied
find: `/proc/2442/task/2442/fd': Permission denied
find: `/proc/2442/task/2442/fdinfo': Permission denied
find: `/proc/2442/task/2442/ns': Permission denied
find: `/proc/2442/task/2443/fd': Permission denied
find: `/proc/2442/task/2443/fdinfo': Permission denied
find: `/proc/2442/task/2443/ns': Permission denied
find: `/proc/2442/fd': Permission denied
find: `/proc/2442/map_files': Permission denied
find: `/proc/2442/fdinfo': Permission denied
find: `/proc/2442/ns': Permission denied
find: `/proc/2471/task/2471/fd': Permission denied
find: `/proc/2471/task/2471/fdinfo': Permission denied
find: `/proc/2471/task/2471/ns': Permission denied
find: `/proc/2471/fd': Permission denied
find: `/proc/2471/map_files': Permission denied
find: `/proc/2471/fdinfo': Permission denied
find: `/proc/2471/ns': Permission denied
find: `/proc/3246/task/3246/fd': Permission denied
find: `/proc/3246/task/3246/fdinfo': Permission denied
find: `/proc/3246/task/3246/ns': Permission denied
find: `/proc/3246/fd': Permission denied
find: `/proc/3246/map_files': Permission denied
find: `/proc/3246/fdinfo': Permission denied
find: `/proc/3246/ns': Permission denied
find: `/proc/4247/task/4247/fd': Permission denied
find: `/proc/4247/task/4247/fdinfo': Permission denied
find: `/proc/4247/task/4247/ns': Permission denied
find: `/proc/4247/fd': Permission denied
find: `/proc/4247/map_files': Permission denied
find: `/proc/4247/fdinfo': Permission denied
find: `/proc/4247/ns': Permission denied
find: `/proc/4249/task/4249/fd': Permission denied
find: `/proc/4249/task/4249/fdinfo': Permission denied
find: `/proc/4249/task/4249/ns': Permission denied
find: `/proc/4249/fd': Permission denied
find: `/proc/4249/map_files': Permission denied
find: `/proc/4249/fdinfo': Permission denied
find: `/proc/4249/ns': Permission denied
find: `/proc/4250/task/4250/fd': Permission denied
find: `/proc/4250/task/4250/fdinfo': Permission denied
find: `/proc/4250/task/4250/ns': Permission denied
find: `/proc/4250/fd': Permission denied
find: `/proc/4250/map_files': Permission denied
find: `/proc/4250/fdinfo': Permission denied
find: `/proc/4250/ns': Permission denied
find: `/proc/4252/task/4252/fd': Permission denied
find: `/proc/4252/task/4252/fdinfo': Permission denied
find: `/proc/4252/task/4252/ns': Permission denied
find: `/proc/4252/fd': Permission denied
find: `/proc/4252/map_files': Permission denied
find: `/proc/4252/fdinfo': Permission denied
find: `/proc/4252/ns': Permission denied
find: `/proc/4254/task/4254/fd': Permission denied
find: `/proc/4254/task/4254/fdinfo': Permission denied
find: `/proc/4254/task/4254/ns': Permission denied
find: `/proc/4254/fd': Permission denied
find: `/proc/4254/map_files': Permission denied
find: `/proc/4254/fdinfo': Permission denied
find: `/proc/4254/ns': Permission denied
find: `/proc/4255/task/4255/fd': Permission denied
find: `/proc/4255/task/4255/fdinfo': Permission denied
find: `/proc/4255/task/4255/ns': Permission denied
find: `/proc/4255/fd': Permission denied
find: `/proc/4255/map_files': Permission denied
find: `/proc/4255/fdinfo': Permission denied
find: `/proc/4255/ns': Permission denied
find: `/proc/4257/task/4257/fd': Permission denied
find: `/proc/4257/task/4257/fdinfo': Permission denied
find: `/proc/4257/task/4257/ns': Permission denied
find: `/proc/4257/fd': Permission denied
find: `/proc/4257/map_files': Permission denied
find: `/proc/4257/fdinfo': Permission denied
find: `/proc/4257/ns': Permission denied
find: `/proc/4259/task/4259/fd': Permission denied
find: `/proc/4259/task/4259/fdinfo': Permission denied
find: `/proc/4259/task/4259/ns': Permission denied
find: `/proc/4259/fd': Permission denied
find: `/proc/4259/map_files': Permission denied
find: `/proc/4259/fdinfo': Permission denied
find: `/proc/4259/ns': Permission denied
find: `/proc/4260/task/4260/fd': Permission denied
find: `/proc/4260/task/4260/fdinfo': Permission denied
find: `/proc/4260/task/4260/ns': Permission denied
find: `/proc/4260/fd': Permission denied
find: `/proc/4260/map_files': Permission denied
find: `/proc/4260/fdinfo': Permission denied
find: `/proc/4260/ns': Permission denied
find: `/proc/4261/task/4261/fd': Permission denied
find: `/proc/4261/task/4261/fdinfo': Permission denied
find: `/proc/4261/task/4261/ns': Permission denied
find: `/proc/4261/fd': Permission denied
find: `/proc/4261/map_files': Permission denied
find: `/proc/4261/fdinfo': Permission denied
find: `/proc/4261/ns': Permission denied
find: `/proc/4265/task/4265/fd': Permission denied
find: `/proc/4265/task/4265/fdinfo': Permission denied
find: `/proc/4265/task/4265/ns': Permission denied
find: `/proc/4265/fd': Permission denied
find: `/proc/4265/map_files': Permission denied
find: `/proc/4265/fdinfo': Permission denied
find: `/proc/4265/ns': Permission denied
find: `/proc/4784/task/4784/fd': Permission denied
find: `/proc/4784/task/4784/fdinfo': Permission denied
find: `/proc/4784/task/4784/ns': Permission denied
find: `/proc/4784/fd': Permission denied
find: `/proc/4784/map_files': Permission denied
find: `/proc/4784/fdinfo': Permission denied
find: `/proc/4784/ns': Permission denied
find: `/proc/7801/task/7801/fd': Permission denied
find: `/proc/7801/task/7801/fdinfo': Permission denied
find: `/proc/7801/task/7801/ns': Permission denied
find: `/proc/7801/fd': Permission denied
find: `/proc/7801/map_files': Permission denied
find: `/proc/7801/fdinfo': Permission denied
find: `/proc/7801/ns': Permission denied
find: `/proc/8848/task/8848/fd': Permission denied
find: `/proc/8848/task/8848/fdinfo': Permission denied
find: `/proc/8848/task/8848/ns': Permission denied
find: `/proc/8848/fd': Permission denied
find: `/proc/8848/map_files': Permission denied
find: `/proc/8848/fdinfo': Permission denied
find: `/proc/8848/ns': Permission denied
find: `/proc/8854/task/8854/fd': Permission denied
find: `/proc/8854/task/8854/fdinfo': Permission denied
find: `/proc/8854/task/8854/ns': Permission denied
find: `/proc/8854/fd': Permission denied
find: `/proc/8854/map_files': Permission denied
find: `/proc/8854/fdinfo': Permission denied
find: `/proc/8854/ns': Permission denied
find: `/proc/8858/task/8858/fd': Permission denied
find: `/proc/8858/task/8858/fdinfo': Permission denied
find: `/proc/8858/task/8858/ns': Permission denied
find: `/proc/8858/fd': Permission denied
find: `/proc/8858/map_files': Permission denied
find: `/proc/8858/fdinfo': Permission denied
find: `/proc/8858/ns': Permission denied
find: `/proc/8962/task/8962/fd': Permission denied
find: `/proc/8962/task/8962/fdinfo': Permission denied
find: `/proc/8962/task/8962/ns': Permission denied
find: `/proc/8962/fd': Permission denied
find: `/proc/8962/map_files': Permission denied
find: `/proc/8962/fdinfo': Permission denied
find: `/proc/8962/ns': Permission denied
find: `/proc/9003/task/9003/fd': Permission denied
find: `/proc/9003/task/9003/fdinfo': Permission denied
find: `/proc/9003/task/9003/ns': Permission denied
find: `/proc/9003/fd': Permission denied
find: `/proc/9003/map_files': Permission denied
find: `/proc/9003/fdinfo': Permission denied
find: `/proc/9003/ns': Permission denied
find: `/proc/9006/task/9006/fd': Permission denied
find: `/proc/9006/task/9006/fdinfo': Permission denied
find: `/proc/9006/task/9006/ns': Permission denied
find: `/proc/9006/fd': Permission denied
find: `/proc/9006/map_files': Permission denied
find: `/proc/9006/fdinfo': Permission denied
find: `/proc/9006/ns': Permission denied
find: `/proc/9009/task/9009/fd': Permission denied
find: `/proc/9009/task/9009/fdinfo': Permission denied
find: `/proc/9009/task/9009/ns': Permission denied
find: `/proc/9009/fd': Permission denied
find: `/proc/9009/map_files': Permission denied
find: `/proc/9009/fdinfo': Permission denied
find: `/proc/9009/ns': Permission denied
find: `/proc/9064/task/9064/fd': Permission denied
find: `/proc/9064/task/9064/fdinfo': Permission denied
find: `/proc/9064/task/9064/ns': Permission denied
find: `/proc/9064/fd': Permission denied
find: `/proc/9064/map_files': Permission denied
find: `/proc/9064/fdinfo': Permission denied
find: `/proc/9064/ns': Permission denied
find: `/proc/9373/task/9373/fd': Permission denied
find: `/proc/9373/task/9373/fdinfo': Permission denied
find: `/proc/9373/task/9373/ns': Permission denied
find: `/proc/9373/fd': Permission denied
find: `/proc/9373/map_files': Permission denied
find: `/proc/9373/fdinfo': Permission denied
find: `/proc/9373/ns': Permission denied
find: `/proc/9607/task/9607/fd': Permission denied
find: `/proc/9607/task/9607/fdinfo': Permission denied
find: `/proc/9607/task/9607/ns': Permission denied
find: `/proc/9607/fd': Permission denied
find: `/proc/9607/map_files': Permission denied
find: `/proc/9607/fdinfo': Permission denied
find: `/proc/9607/ns': Permission denied
find: `/proc/9754/task/9754/fd': Permission denied
find: `/proc/9754/task/9754/fdinfo': Permission denied
find: `/proc/9754/task/9754/ns': Permission denied
find: `/proc/9754/fd': Permission denied
find: `/proc/9754/map_files': Permission denied
find: `/proc/9754/fdinfo': Permission denied
find: `/proc/9754/ns': Permission denied
find: `/sys/fs/fuse/connections/8388611': Permission denied
find: `/sys/fs/fuse/connections/8388610': Permission denied
find: `/sys/kernel/debug': Permission denied
find: `/tmp/pulse-PKdhtXMmr18n': Permission denied
find: `/var/spool/cups': Permission denied
find: `/var/spool/cron/atjobs': Permission denied
find: `/var/spool/cron/crontabs': Permission denied
find: `/var/spool/cron/atspool': Permission denied
find: `/var/log/samba/cores': Permission denied
find: `/var/log/speech-dispatcher': Permission denied
find: `/var/cache/system-tools-backends/backup': Permission denied
find: `/var/cache/ldconfig': Permission denied
find: `/var/lib/udisks2': Permission denied
find: `/var/lib/lightdm': Permission denied
find: `/var/lib/mdm': Permission denied
find: `/var/lib/sudo': Permission denied
find: `/var/lib/polkit-1': Permission denied
/etc/thunderbird
find: `/etc/cups/ssl': Permission denied
find: `/etc/ssl/private': Permission denied
/etc/apport/blacklist.d/thunderbird
/etc/apport/native-origins.d/thunderbird
find: `/run/wpa_supplicant': Permission denied
find: `/run/udisks2': Permission denied
find: `/run/cups/certs': Permission denied
/usr/share/doc/thunderbird
/usr/share/indicators/messages/applications/thunderbird
/usr/share/lintian/overrides/thunderbird
/usr/lib/thunderbird
/usr/lib/thunderbird/thunderbird
/usr/bin/thunderbird
find: `/root': Permission denied
find: `/home/lost+found': Permission denied
Como lo hice sin sudo pues por eso salen eso de "Permission denied", y esto es solo un poco de los resultados, asi de es de compleja una instalacion desde repositorio, pues se enlaza todo con todo, en lo personal no me gusta instalar tanto con repos, precisamente por lo complicado que se vuelve modificar un una aplicacion sin que afecte otro pedazo de sección de tu kernel u otra aplicacion.
Soy más de los que gusta de coger un paquete aparte, compilarlo y ejecutarlo desde una carpeta que yo elija, en fin, poco a poco le cogeras gusto a linux, se ve que tienes ganas y empeño, solo te falta motivacion, conocimiento y experiencia.