Most of our applications work 'correctly' in that you log into Apex developer (20.1), hit 'run application', log into the application as an app user, and the developer and application tabs are 'linked' and both logged in - the app has the developer toolbar at the bottom, and you can switch back and forth between the tabs.
ONE of our applications however, behaves differently.
Log into Apex Developer and hit 'run application', this brings up the application login page with developer toolbar
Log into the application, and the home page is displayed without the toolbar.
The Developer session has now been logged out, and needs to log back in, and hit 'Run application' again.
Application session appears, already logged in as the application user, and 'linked' to the developer session as expected, and now everything works fine.
And as a final quirk, if you log out of the application, then it logs out the developer session too.
Anyone else come across anything similar and have any thoughts on anywhere to start looking?