https://bugs.freedesktop.org/show_bug.cgi?id=90264
--- Comment #10 from Matt Whitlock freedesktop@mattwhitlock.name --- Whenever a context menu in Chromium fails to display correctly (shows as solid black instead), the following lines (or similar) are appended to the kernel message log:
nouveau E[chrome[5932]] multiple instances of buffer 249 on validation list nouveau E[chrome[5932]] validate_init nouveau E[chrome[5932]] validate: -22
Does not happen upon display of corrupted tooltips, only context menus.