4.8.3

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- Tasklist: Work around segfaulting of group buttons.
- Tasklist: Properly initialize the monitor geometry on startup (bug #7340).
- Use portable abicheck.sh from xfconf.
- Panel: Avoid recursing gtk_main_quit() on signal.
- Tasklist: Hide wireframe when window is destroyed (bug #7377).
- Directorymenu: Remove unused varaible.
- Pager: Fix typo in row warning.
- Tasklist: Fix function prototype.
- Panel: Do no inline function.
- Tasklist: add button release event to proxy item (bug #7362).
- Translation updates (zh_CN, tr, de).