Going from 25.2.1 to 25.2.2 there is a problem, deepseek describes it like this:
"Vaadin 25.2.2 bumps Vite from 8.0.16 to 8.1.3. Rolldown’s default minifier (used in production builds) mishandles CKEditor 5’s Arabic localized strings — backtick template literals containing RTL Unicode text get mangled into invalid JavaScript. The resulting SyntaxError in the lazy-loaded vaadin-confirm-dialog-*.js chunk breaks the dynamic import chain, leaving the blue progress bar spinning forever. "
I can’t really confirm this is actually the problem but going back to 25.2.1 problem disappears.
CK editor version 5.3.0 and 5.3.1