Sorry for the late response, I'm doing 16+ hours a day working on the upcoming release 🙂
I've investigated this issue as well, and it seems like it originates from a recent change in the script + when the search box model was changed to 'content-box' from 'border-box' it made it extremely hard to get it right. I may have found a possible solution, but it involves changing core files, including JS and CSS too.
If you don't mind waiting 1-2 days for the upcoming release to be approved, that would be great. That should resolve the calculation issues, hopefully once and for all.Best,
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