When doing "/usr/lib/qubes/xdg-icon git-cola 512" (or any other max size, instead of 64) the result points to a .svg file of size 612x578.
After commenting line 8 of qubes.GetImageRGBA (to avoid forcing a max size, which creates wrong icons for most user-installed apps, i.e. Thunar, Meld, etc.) we need to make this modification to avoid not creating icons ("Failed to get icon for git-cola.desktop: Image size constraint violation: width=612 height=578 max_width=512 max_height=512) for this large svg files with no smaller option.
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