I'm running Pro 2.3.6 and have been seeing some odd issue when adding text elements in particular. They somehow get "linked".
When I modify text in one text element, the other text element displays the same text.
If I delete the other text element, the first one also deletes.
Its as though they both are sharing the same ID of some sort.
Usually at that point I have to reload the content builder for things to resolve themselves.