Steps to reproduce:
Create a page in at least two different versions (v1 and v2).
Open the page in v1
Switch to the Viewport view and select a different version than in the Confluence view.
Click on "Edit Page"
You can edit the page in the selected version(v2) from Viewport. The displayed content matches the version displayed in the upper right corner of the edit mode.
The version indicator on the right hand side shows the version from the latest context in Confluence(in this case v1) which does not match with the content necessarily.