I have rules moving emails in various folders on my email account. When searching one of these folders, Airmail snaps back to my inbox folder after some time. This can happen immediately or after a few moments. With this bug, it is impossible to read longer mails in a folder or even scroll through mails in a folder since you will be randomly snapped back into the main inbox. I made a short screencast to demonstrate the issue: http://sharedby.ralphcibis.de/QAtG4/5oAtYBX9

Same happens on my colleagues Mac. Both running on Sierra.