Hi,
TablePress uses both add_shortcode()
and apply_shortcodes()
, as they are used for different purposes. add_shortcode()
is used to register the [table]
Shortcode, while apply_shortcodes()
(or rather do_shortcode()
, for which that is an alias function) is used to evaluate other Shortcodes in table cells.
I highly doubt that this is a problem in WordPress Core. Many, many more sites would then show this problem, and not just yours.
It could also be a problem with PHP on your server, e.g. if regular expression parsing in it is somehow broken.
Therefore, please try if other Shortcodes work. Also, please check the server error log files. And finally, please try with everything updated. If it’s not yet possible to update your main site, maybe set up a test site with the same versions of everything (but installed from a fresh download) on the same server.
Regards,
Tobias