I'm not sure if this should be an issue for core Claro or contrib Paragraphs, but it only seems to manifest with Claro, so starting here.
A fresh install of Drupal 8.9.0-rc1, paragraphs 1.12 with Claro theme enabled as an admin theme.
Added a paragraph type with a text field to an article.
When creating an article, and reducing width of the browser, the title field overflows under the options tabs to the right.
See attached screenshot.
I've looked for duplicates and tried patches from related issues, but I can't see anything that describes this behaviour exactly.
I've added possibly realted issues.
PHP 7.2, Ubuntu 20.04 , Firefox / Chrome