Really sorry to read that reply from Basj.
Ironically, this is the only messed-up feature in the whole Windows 11 Taskbar fiasco that actually matters to me. The omission of "NeverCombine" has damaged the new OS so badly for me that I will not be installing W11 on my PC until this is rectified or I am assured of an alternative. I came to Stardock 11 website, specifically looking for this feature.
Why? Because I use the "Never Combine" feature extensively. The facility to visualise and track all open windows has existed since Windows XP and is a significant productivity tool. I work very visually and need to have all my tasks visible to me, so that I can pick them efficiently and deal with them. If there are many tasks and therefore too many icons on the Taskbar, I just open another layer of the Taskbar. Long ago, when Windows XP was new, I experimented with stacking the windows and this was a disaster - I kept forgetting tasks, duplicating work, missing deadlines and generally messing my work so much that I have permanently left Never Combine windows on, now for over a decade.
I might explore the Registry hack (#Sharma261), but I was hoping for an off-the-shelf solution - and registry tweaks tend to get disabled at the next Windows Update.
For now, I'll stay with W10 and look forward to the next version of Stardock 11.