Comment 15 for bug 1406725

Just discovered something while working on bug 1513815

Basically, i was running pd on N4 set this env variable
SAL_USE_VCLPLUGIN=gen
which according to bjoern "forces LO to ignore the gtk plugin and uses the old and trusty X11-only backend" ...figure this is true for all Xapps?
anyhow, i launched FF in full screen mode...no corruption, then connected mouse...i see corruption...moused to full screen, no corruption. but there's a black bar when no corruption, but the contents are all shown...
see video as it's easier to understand
https://www.youtube.com/watch?v=PHbyv25Ekx0