HideElements can be deactivated temporarily by simply adding ?hideelements=false to the end of your URL:

URL

https://confluence.example.com/display/Example+Page

URL + Parameter

https://confluence.example.com/display/Example+Page?hideelements=false

If your URL already has parameters in it, you can append another one by using & instead of ?:

URL

https://confluence.example.com/pages/viewpage.action?pageId=123456

URL + Parameter

https://confluence.example.com/pages/viewpage.action?pageId=123456&hideelements=false