4.20.8

- wayland: Set layer-shell namespace
- wayland: Restart panel when gtk-layer-shell is in unrecoverable state
- Use XfwMonitor to match monitor by name
- Refactor XfwScreen management a bit
- clock: Deduce update interval from date and time formats
- Fix autotools build
- Set translation domain for plugins
- Remove G_GNUC_CONST (complement)
- Remove G_GNUC_CONST
- libxfce4panel: Do not emit signals if construct() has not been called
- I18n: Update po/LINGUAS list
- Fix -Wdiscarded-qualifiers compiler warning for autotools builds
- build: Replace wrong define guard with libxfce4ui version check
- panel: Use same code to cleanup plugin config everywhere
- icons: Fix non-zero page opacity
- panel: Set itembar clip when allocating window
- I18n: Update po/LINGUAS list
- actions: Fix variable used out of scope
- pager: Fix workspace switch for Compiz when scrolling over pager
- build: Do not display full path in generated headers
- Translation Updates:
  Azerbaijani, Catalan, Georgian, Greek, Italian, Lao