Upgraded from 4.2.1 to 4.2.2 on clone site - what are common issues less noticeable?
 

...and everything seems to have gone well, so will be doing it on my live site. What are some issues that are commonly happening, so that I can double check the less obvious ones? Perhaps things that do not appear obvious but fail once looked at or clicked on, etc? Thanks

Declaration errors.

Ok, thanks. I did not see any declaration errors at the top of the page. To see these, would I need to change the errors to show? If so, is this in the config file? Or where? or will the declaration errors show regardless? So, can I safely assume that since I have no declaration errors that I'm good to go? I did notice that in the admincp that it still shows 4.2.1 for the admin cp version, but on the forum index it does show the 4.2.2... thanks!

That is because rather than having customers complain about shoddy code they disabled all warnings in the class_core.php

Look for

define('SKIP_ALL_ERRORS', true);

and / or

define('SKIP_DS_ERRORS', true);

So, change those to true? Are they false by default? Thanks.