[dwm] Greyish blobs

When running Mathematica 6, two "greyish blobs" (see screenshot) appear
(at least one of those seems to be the Mathematica kernel as the window
aka "blob" disappears when shutting that down). Those windows appear in
front of all unfloated clients, but behind all floated ones, they don't
take focus in any form (moving mouse over them doesn't give them focus,
and the previously focused window stays focused) and they appear on all
tags (the indicator shows they aren't assigned to any tag).

Attached I provide a screenshot of the situation, and xprop-listings of
both the Mathematica main window and of one of the "greyish blobs". Any
help or advice in this matter is appreciated (as my dwm-session becomes
unusable when trying to work with Mathematica, unless I switch to float
mode).

Regards,
Sebastian

• text/plain attachment: math.main.txt

• text/plain attachment: math.blob.txt

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