Problem:    "textlock" is always zero.
Solution:   Remove "textlock" and rename "textwinlock" to "textlock".
            (closes #10489)

Problem:    Syntax regexp matching can be slow.
Solution:   Adjust the counters for checking the timeout to check about once
            per msec. (closes #10487, closes #2712)

Problem:    Error for missing :endif when an exception was thrown. (Dani
            Dickstein)
Solution:   Do not give an error when aborting. (closes #10490)

Problem:    Vim9: a few lines not covered by tests.
Solution:   Delete dead code.  Add a few test cases. make "12->func()" work.

Problem:    Vim9: a few lines not covered by tests.
Solution:   Add a few tests.

Problem:    Using freed memory with "]d".
Solution:   Copy the pattern before searching.

Problem:    Substitute overwrites allocated buffer.
Solution:   Disallow undo when in a substitute command.

Problem:    'completefunc'/'omnifunc' error does not end completion.
Solution:   Check if there was an error or exception. (closes #10486,
            closes #4218)

Problem:    Build fails with normal features and +terminal. (Dominique Pellé)
Solution:   Add #ifdefs. (closes #10484)

Problem:    Using 'imstatusfunc' and 'imactivatefunc' breaks 'foldopen'.
Solution:   Save and restore the KeyTyped flag. (closes #10479)