If the screen resolution and font scaling had screw-up the appearance
of «okular», you can create an executable file

~/.local/bin/okular

with the following content:

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QT_SCALE_FACTOR=1.2 /usr/bin/okular "$@"
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Adjust the scale factor to Your needs.


Check the order of $PATH (file ~/.bash_profile). It must contain somthing
similar:

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PATH=$HOME/.local/bin:$HOME/bin:$PATH
export PATH
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