请问，看网页视频时，我全屏了，看完了，怎么退不出全屏。。？？

libglib2.0-0: Depends: libffi6 (>= 3.0.4) but 3.0.10~rc8-5 is to be installed
Depends: libpcre3 (>= 8.10) but 8.12-3ubuntu2 is to be installed
Depends: zlib1g (>= 1:1.2.2) but 1:1.2.3.4.dfsg-3ubuntu3 is to be installed

Could not calculate the upgrade

An unresolvable problem occurred while calculating the upgrade.

Please report this bug against the 'update-manager' package and include the following error message:
'E:Error, pkgProblemResolver::Resolve generated breaks, this may be caused by held packages