System 'back' button not working on Android devices. Seems it's been a known issue for a while. This means you scroll down your newsfeed, click on comments to read or post a comment and you're stuck there. You can't go 'back', leaving you with no option but to close the app and restart it. Problem started spontaneously using the last version of the app, which prompted me to update to the latest version to discover there is no change. Perhaps not the app, but something at the 'Facebook end'
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