[0.4.14][NTUSER][3DTEXT] Squashed backport CORE-17866, CORE-8217

[0.4.14][NTUSER][3DTEXT] Squashed backport CORE-17866, CORE-8217

The main part in [USER32] was already committed into 0.4.14-RC-123-g 75e9ac772756676f82666e0d26f7c5e6c6d0f4ed
but we do have two follow-ups that are worth picking as well:
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[NTUSER] Do not remove message from the Msg Queue if it is not for us. (#4129)

CORE-8217 This part of the fix keeps the buttons working (Cancel/Ok/top-Right-X) even under high CPU-load
Patch from 'I_Kill_Bugs' contributor.

Fix picked from 0.4.15-dev-3499-g 7d1b50394b90b94f5d08ecb2b248e421ae2a1c5d
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[3DTEXT] Fix 3dtext.scr using near 100% CPU (#4125) CORE-17866, CORE-8217

Fix picked from 0.4.15-dev-3443-g 5c9fdcb1de7faa49c2af341631217baa7b9fe552