Suggested by Wakako Watanabe – New
Currently, MultiSelect option set pull-down menu can only display "Select All" and four option sets.
If we have set 5 or more option sets, we need to scroll the 5th and subsequent options to display them.
This scrolling is also inefficient if you have set a lot of option sets, so if you can customize the size of the pull-down menu, you can expect more efficient work.