Thunderbird and disappearing cursor

[ToddAndMargo]

Hi All,

52.9.1 (64-bit) for Fedora 28
Xfce 4.12

When composing a letter in Thunderbird and I wait too long, I lose
my cursor.  It is especially annoying when trying to reposition
the cursor with my mouse.

Is this an Xfce thing or a Thunderbird thing?


Many thanks,
-T

-- 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Serious error.
All shortcuts have disappeared.
Screen. Mind. Both are blank.
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