Forum Post breaks when you add two images at once.

When you add two images at once with the “insert image” funcion the post just breaks in really weird and inconsistant ways. Sometimes not letting you skip lines or deleting big sections of your text with the press of a letter or sometimes not even letting you click anything anymore.
Only closing and completly redoing the post works, and since it won't let you copy stuff anymore as well a long post can be lost due to this.
Although the post can still be posted without issue. 

I am using Google Crome on Desktop in case that is important.