XRandR lets games adjust the display resolution as needed. It is strongly recommended to install it if you plan to use games.
On CrossOver 17 and greater, the simplest solution to fix this issue is to run: /path/to/cxoffice/bin/cxfix missinglibxrandr missinglibxrandr.amd64
Or add --show-all to see how CrossOver would fix it on your platform and others.
Alternatively you may try one of the commands below.
The commands usually also apply to newer versions of the distributions above as well as derived distributions. So for instance a fix for Debian 7 may still be valid for the latest Debian Testing and is typically also applicable to Ubuntu, Linux Mint, Deepin and Pop! OS. Similarly a fix for Fedora likely also works on Red Hat Enterprise Linux, CentOS, etc.
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