My org uses Jira Cloud (Premium). Over the last couple of weeks, the default search JQL query changed.
This is the one that loads when the top right search bar is used:

Past setup
text ~ "searchterm*" ORDER BY Created DESC
Current setup
summary ~ "searchterm*" OR description ~ "searchterm*" ORDER BY Created DESC
These yield two very different results. Most importantly, the past setup query, searches in custom fields. The new query does not.
Can this behaviour which worked well and changed without any notice be customised / reverted / opted out of?