Staff Answer

May 31, 2017 - 10:44 AM
Imagine you do a website redesign to a new template, but all the content stays the same, you will not experience a ranking reindex. Usually ranking reindex is triggered due to title change or your body content changes 70% that is visible to the user.
As long as your H1, H2 and the rest of the header tags remain the same, you will not trigger Google Reindex.
Quoting user softplus:-
Hi Bill
Hidden text when misleading and off-topic can result in penalties and bans. It is however almost impossible for Google to determine whether or not text is misleading and hidden automatically. If your page's user interface depends on hidden elements that is generally not a problem (but it might result in your pages being indexed suboptimally - eg when you have several text-elements on the same page all accessable through the same URL).
You can easily confirm that Google indexes hidden content like that by placing unique text in one of those blocks, waiting for the page to be re-indexed and then searching for it.
The reason Google reacts so strongly against misleading hidden text and links is because they do index them correctly (and therefore they do "work"). If Google were to just ignore hidden text, many sites would try to use it. By giving a strong penalty (or even ban) the risk involved with using hidden text to gain advantages is often larger than the possible gain. (not to mention that you can usually just put the same text in the visible sections of your pages anyway!)
If your hidden content is NOT sneaky, misleading, off-topic, etc then you should have nothing to worry about. Many sites use hidden content in one form or other as critical parts of the interface.
John
In worst case scenario if Google does trigger a reindex. You should not lose a ranking if your content is as well as optimized as before. It may move a spot up or down or remain the same. But it will not disappear unless the link no longer works.