Start11 1.31 changelog
The line on 22H2 taskbars now adjusts with the alpha set on the taskbar by the user and is hidden entirely when the taskbar is on top. You can also create a registry key in the usual location of type string and give it a value of "1" and a name of "HideTaskbarLineEntirely" should you wish to always hide the line entirely.
Problem for me is (on all three of my systems) that the line is hidden entirely (EDIT: no, I do NOT have it on top position) even WITHOUT having the Start11 Taskbar activated and WITHOUT my consent. But I want to have the line and did not find a way to get it back, short of reverting to 1.30.
Found some other issues, too (since I bought Start11 when 1.30 was "current", that version is my point of reference):
1.) When Start11 search is disabled, the search box of the Win11-type start menu vanishes; the "hide search box" toggle option is not respected (i.e. I set it NOT to hide the search box, but it is still gone; toggling on/off with restarting between changing settings does not help). Sometimes, but not always, when I type something to search for, nothing happens. This bug is also present in 1.30.
EDIT: Screenshot
2.) For some menus, dark mode is not correctly applied, e.g. shutdown menu, Start11 taskbar right click menu. My system is set to dark Windows mode, but light app mode. (do not know if these descriptions are correct; I use the german version of Windows 11). When I apply dark app mode, too, the menus have correct dark color, so I suspect the menu color is derived from the wrong color setting (app mode instead of Windows mode). Win+X menu as well as right click menus on the start menu (tested with Win10 and Win11 start menus) have correct dark color. When not using Start11 taskbar, the correct dark color is displayed for the taskbar right-click menu (no wonder, as it is controlled by Windows and not Start11). Also present in 1.30
EDIT: Screenshots (Shutdown Menu as an example)
Start11 vs. Windows default:
My Windows dark/light mode settings:
3.) Win11 Start Menu: When I move Icons between groups (not folders!) and move it to another group, everything works fine. But when I move a second icon to the same group, the previously moved icon is put to the beginning of that group. When I move a third one, both previously moved icons are put to the front, ignoring my (re-)arrangement. If I close the start menu and re-open it between movings, my arrangement is saved and everything is okay, so I suspect that the arrangements are not saved after each moving of icons. Don't know if it was present in 1.30, too. Noticed it after the update to 1.31, but actually, I prefer the Win10 style menu.
EDIT: Screenshots
EDIT:
4.) (more of a extensions/generalization to my problem with the taskbar appearance described in the beginning) Start11 interferes with the appearance of the taskbar without my approval. When the system boots up and the login animation is running, the taskbar looks exactly as I want it (i.e. the Windows default). But after 1-2 sec., Start11 kicks in and you can see some slight changes in color and transparency, the clock shows seconds (which is okay, because that is the one feature I actually want) and the border/line at the top of the bar disappears. All this despite the fact that I have not enabled the Start11 taskbar!! Even with unchanged appearance settings in the Start11 configuration tool (see screenshot). Version 1.30 respected the Windows default settings. If this (new) behaviour is intended, please give us an option to prevent any messing around with the taskbar appearance, because I (and maybe a lot more who do not post here) like the Windows default appearance of the taskbar just the way it is (+ clock showing seconds). 
Windows default:
After Start11 kicks in:
If you look closely, you notice that the taskbar appears darker (more black instead of dark blue) and less transparent.
I hope the new screenshots help you fixing these things.
Best regards
