Problem:    No error when using alpha delimiter with :global.
Solution:   Check the delimiter like with :substitute. (closes #8415)

Problem:    Build problems with MSVC, other crypt issues with libsodium.
Solution:   Adjust MSVC makefile. Disable swap file only when 'key' is set.
            Adjust error message used when key is wrong.  Fix Coverity issues.
            (Christian Brabandt, closes #8420, closes #8411)

Problem:    No error if a function name starts with an underscore. (Naohiro
            Ono)
Solution:   In Vim9 script disallow a function name starting with an
            underscore, as is mentioned in the help. (closes #8414)

Problem:    Coverity reports a memory leak.
Solution:   Fix the leak and a few typos. (Dominique Pellé, closes #8418)

Problem:    Vim9: crash when using operator and list unpack assignment.
            (Naohiro Ono)
Solution:   Get variable value before operation. (closes #8416)

Problem:    GUI mouse events not tested.
Solution:   Add test_gui_mouse_event().  Add mouse tests. Also add a few
            viminfo tests. (Yegappan Lakshmanan, closes #8407)

Problem:    Vim9: breakpoint in compiled function not always checked.
Solution:   Check for breakpoint when calling compiled function from compiled
            function.

Problem:    Vim9: cannot set breakpoint in compiled function.
Solution:   Check for breakpoint when calling a function.

Problem:    Not enough tests for quickfix end_col and end_lnum.
Solution:   Add a few more test cases. (Shane-XB-Qian, closes #8409)

Problem:    execute() function test fails.
Solution:   Adjust test for different error.