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A note for bibisectors.
Please note that if your bibisection resulted in commit ebf767eeb2a169ba533e1b2ffccf16f41d95df35, this means that your bibisection result is incorrect!
That was not a commit that has caused any regression: that was a commit that made the problem apparent. The corruption happens on save stage; this commit caused already corrupt files to emit errors/warnings on load time.
So please re-bibisect, this time paying attention not to the error dialog, but to the document content, which, in case of corruption, would be truncated on load.