Please help us help you and fill where relevant:
Your LimeSurvey version: LimeSurvey Community Edition   Version 6.2.10+231004 
Own server or LimeSurvey hosting: own server
Survey theme/template: Fruity
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When I edit a question from the menu at the right of question line (see attach file : (creenshot N°1) i get following message : "400 : Mauvaise requête Votre requête est invalide.
La requête ne peut pas être interprétée par le serveur à cause d’une syntaxe mal formée.Veuillez ne pas répéter la requête sans modification.
Si vous pensez qu’il s’agit d’une erreur du serveur, veuillez contacter Administrateur."

google translated:
"400: Bad request Your request is invalid.
The request cannot be interpreted by the server due to malformed syntax. Please do not repeat the request without modification.
If you think this is a server error, please contact Administrator."

I've done a "comfort update" yesterday and before I Don't get this issue. 

If I access editing from "structure" TAB, it works (see screenshot N°2)

Thanks for any help ?
Best regards

Please file a bug report - bugs.limesurvey.org/

bugs.limesurvey.org/view.php?id=19153