I came across the following. When you’re on a post with multiple tabs and a field from a different tab gets a validation error on publishing, the page will not switch to that tab. Not a major issue, but I think it would be nice if it did. If there are multiple tabs with errors, I think going to the first tab with an error would be the most logical option.
There could be multiple validation errors across multiple tabs, but I agree with what I assume is the basis of followalter’s suggestion: it can be difficult to locate a validation error when there are many fields, particularly when there are accordions and tabs.
So a related suggestion: list the label of each field that fails validation in the “components-notice” at the top of the page.
I just wrote a script that does this and, as usual, it took me longer than I would like to get it right.
It would be great if this were built into ACF, so you know immediately which field(s) failed validation before hunting through tabs and accordions.