Hi @Nitruc
Thanks for the bug report.
I have done some testing which you too can replicate.
If you place your cursor into the title and hit tab, the cursor remains for a split second (long enough to type another character) before skipping ot the the_content.
If you try this same process on an ACF text field, there is no lag.
The lag is definitely a jQuery event on the blur event of the title text field. I’m not sure I can override this as it is built into the WP core.
Thanks
E