Deprecated function: strlen(): Passing null to parameter #1 ($string) of type string is deprecated in Drupal\glossify\GlossifyBase->parseTooltipMatch() (Line153 in /src/GlossifyBase.php)

Thanks, yes should be investigated and fixed, please.

This shouldn't happen. "ignore_tags" has their default setting defined in the Doctrine Annotation above each filter plugin. So "ignore_tags" should always resolve at least to an empty string, not NULL. Maybe a simple clear all caches will fix the issue?

There is no need for an update hook, since this is a plugin. Filters never implement "defaultConfiguration()" for some reason. Not here nor in core. They are always defined in the doctrine annotation / PHP Attributes.

Talked with @anybody internally. Not really worth taking a deeper look at this.