Adding new post: not able to add link to text + removes dashboard scrollbar

Have tried deactivating recent plugins (e.g. Ninja Cache and similar) with no improvement. In last couple of days I have not been able to add links within my posts.

1. When in WP dashboard adding new post I highlight text I want to add link to.
2. I click on ‘insert/edit link’ but the box to enter URL doesn’t open and the scrollbar taking me further down the page disappears.
3. The ‘insert/edit link’ and ‘remove link’ buttons are now greyed out and no longer clickable.

This happens with past posts I try editing as well as new ones.

Anyone else had this?

…also looks like it isn’t letting me save post tags.

Thanks Alin – I deactivated then re-added one by one all the plugins, the troublemaker was ‘MaxButtons’ so now everything is fine.

Thanks for your help.