When an app disappears after some data from it has been copied to the
clipboard, the owner of the clipboard selection becomes a new memory
selection source. The initial reference this new selection source is
never unref'ed, which leads to this being leaked on the next clipboard
selection owner change.
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1293
Support for them appears to be way less common than e.g. png, which is
currently the preferred format from Firefox, Chromium, Libreoffice and others.
Adopt to that fact.
As a side effect, this works around a bug observed when copying images in
Firefox on Wayland.
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1141
Most usually, applications either expose clipboard content either as text
or as images, so the prioritization here is pointless. However there's some
outliers like LibreOffice Calc which exports content as both image and text
formats (besides other internal ones).
In that mixed case, we probably prefer to keep text formats, rather than
image based ones.
Closes: https://gitlab.gnome.org/GNOME/mutter/issues/919
This is a simple clipboard manager implementation on top of MetaSelection.
It will inspect the clipboard content for UTF-8 text and image data whenever
any other selection source claims ownership, and claim it for itself
whenever the clipboard goes unowned.
The stored text has a maximum size of 4MB and images 200MB, to prevent the
compositor from allocating indefinite amounts of memory.
This is not quite a X11 clipboard manager, but also works there.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/320
