If a user does not have JavaScript enabled, the CookieWarning notification bar is visible but isn't dismisable with the "OK" button, it simply does nothing when clicked.
The notification bar should hide when the user clicks the OK button, no matter if JS is enabled or not.
https://www.mediawiki.org/wiki/Extension:CookieWarning shows a link to Example https://www.droidwiki.org/. droidwiki is mentioned here since its admin is the same person as the developer of mediawiki extension MediaWiki-extensions-CookieWarning.
On droidwiki with javascript disabled (noscript enabled) when pressing the OK button, the cookie warning doesn't disappear.
https://www.droidwiki.org/wiki/Spezial:Version shows mediawiki version:
1.36.0-wmf.33 (rMW2605e79a80c4)
20:43, 3 March 2021
and MediaWiki-extensions-CookieWarning version:
0.3.0 (4f6c27f)
08:51, 22 February 2021
Similar to previous T145647. Creating a new ticket as suggested in T145647#6892109.