Just upgraded from 5.19.2 to 5.20.0. Upgrade appeared to run through without a hitch.
Joomla! 3.9.13, php 7.3.12, mySQL 5.7.28
Now, when editing existing email address, or when entering new contact details, saving fails with the following error message:
Please correct the following errors in the form fields below:
Email is not valid.
There's no corresponding error in the CiviCRM error log. Looks like the email address check isn't working properly. Has anyone else seen this?
[Edit] As a temporary solution, I have commented out line 62 of civicrm/CRM/Contact/Form/Edit/Email.php (the line which begins "$form->addRule"), but this is obviously only a stopgap.
[Edit] Upgraded to 5.20.1 and the problem persists.
[Edit] Problem is fixed in 5.20.2. So it was possible to upgrade directly from 5.19.2 to 5.20.2, but to upgrade to any of the intervening releases, the patch is needed. https://github.com/civicrm/civicrm-packages/pull/271.patch