Hi all - This was reported a few days back and a fix has already been worked and it’s awaiting release. I am the engineer leading our Confluence effort to adopt theming with design tokens. This style change was slightly errant as we’ve been methodically updating the Confluence codebase to be capable of displaying different themes. For a status on the fix, please follow https://jira.atlassian.com/browse/CONFCLOUD-75937
On the topic of theming….if you haven’t already, please take a look at our announcement for theming being available to preview for the Developer Canary Program: 
Announcing Confluence Cloud Theming Preview for Developer Canary Program