Yes I know, this is technically not a direct answer to the specific question, and I realize that... however, I think it's fairly reasonable in this use-case to point out that unless you need to physically see the tab as the Flow runs, there's really no need to navigate across browser tabs.
When you use the Action Create new tab, it stores that tab into a new web browser instance variable. If you're using defined UI elements from each page for basic stuff like clicking buttons, scraping data or inputting text, then PAD can interact with the elements on those tabs even if they're not visible by using the correct instance variable.
I tested these two Actions in Chrome which returned successful results from the 2nd tab while 3 tabs were opened and the 3rd tab in foreground the entire time.
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Just to make sure, I also tested If text on screen (OCR); and even though I expected it to fail since the necessary text was on a background tab, it actually succeeded the first few times. This really had me going for a minute! Until I realized it was identifying the target text from it's own block in the PAD Designer window itself on my second monitor... yea I'm a dummy 🤣