Simply run Pi with the FYNE_THEME environment variable to light. Like so:
FYNE_THEME
light
FYNE_THEME=light pi-im
You can also do the same for a dark theme:
FYNE_THEME=dark pi-im
Windows follows the exact same layout but with different commands.
set FYNE_THEME=light pi-im.exe
set FYNE_THEME=dark pi-im.exe
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