[tlu] Overlay messages no longer transparent?

[Bruno Voisin]

Applying an update just now, I've realized an overlay message ("Infrastructure update successful") wasn't transparent, effectively hiding the list of available package updates below. See the attached screenshot.

I don't remember noticing this in the past, so it must be relatively new. All this with macOS 10.13.5.

By the way, "succés" in the French version of the message should be "succès" (with a grave accent, not an acute one).

Bruno