This is good detective work, radient. Apparently the icons at the top are a variation of the spell timers found in various other UIs. As you discovered, they are added above the normal Maintained tiles when they are dropped onto Hotbar 10.
The icons are partially cut off in my example, but in playing around with the feature it looks like the bars do work for spells that have timers:
When you describe it as two windows mashed together, that's pretty much what it is -- a spell timer and the ProfitUI Maintained window. Not long ago a variation of the DrumsUI spell timer window was added to ProfitUI_CE, which gives basically the same result as the "extras" code, except that the icons with timers appear in a separate window and you add spell names manually to the configuration text file instead of using hotbar 10. Hotbars are at a premium these days, so for a lot of users it may make more sense to use the separate window for their timers.
Looking at the files on the server, it appears that players were getting the hotbar-10 feature whether or not they chose it from the variants. I went ahead and made some changes that will allow players to choose whether or not they want to use the hotbar 10 spell timers. Note that only the left-aligned default ProfitUI maintained window actually uses any of this.
Since as of today every ProfitUI_CE user has the hotbar-10 code, I changed that to the default choice, with "no extras" as a variant. Now when you choose "no extras" you will actually get no extras, and you can use the ProfitUI left-aligned default maintained window without avoiding hotbar 10.
Try this out and post again if you see anything wonky with it.