Merges for GHC 8.8

Merges for:

• #16287 (closed)
• #16279 (closed) (!284 (closed))
• #16255 (closed) (!260 (merged))
• #16183 (closed) (!121 (merged))
• #16077 (closed)
• #16193
• #15849 (closed) (!330 (merged))
• #15733 (closed)
• #15549 (closed), #14729 (closed) (!208 (merged))
• #8657 (closed) (!219 (closed))
• #16195 (closed) (!131 (merged))
• #16225 (closed), #16188 (closed), #16204 (closed) (!207 (closed))
• #16141 (closed)
• #16180 (closed)