More backports for GHC 9.10.1

Backports:

• !12393 (closed)
• !12284 (closed)
• !12267 (closed)
• !12344 (closed)
• !12340 (closed)
• !12387 (closed)
• !12376 (closed)
• !12368 (closed)
• !12328 (closed)
• !12358 (closed)
• !12316 (closed)
• !12177 (closed)
• !12308 (closed)