When making comments or replying to comments on the document (Collabora Online Development Edition) the page immediately jumps to the beginning of the document. This happens whether I am typing directly in the comment box or pasting text there. (C.O.D.E., LOOLWSD 1.9.8)
CODE has been updated recently to 2.0.1, please try with the new version. I could reproduce the issue with an old CODE (1.8.5 IIRC), but not on a server based on the current version, so marking this as WORKSFORME.