It is the new Gmail update (Gmail 2.3.5) with the signature permissions removed. All the widgets and apps that used the Gmail content provider are now able to read it again.
1. Uninstall Gmail (I usually clear data then uninstall)
2. Uninstall any app that needs to connect to the content provider. (Any app that stopped working after the Gmail update.)
3. Reboot phone.
4. Install the APK from above. (Gmail 2.3.5 with normal permissions)
5. Install your apps back.
NOTE: Google did change around labels somewhat. So just an FYI if some apps still dont work. They may not be able to tell what is unread. But I am guessing most apps just went for the unread count which still should be there.
NOTE2: You have to uninstall the other apps because of the way android asks for permissions. It may only do it once... I am not positive.
NOTE3: Good luck... This is all reversible as you should not even need root to do it. (I have not tested an unrooted phone) But I dont see why it wouldnt work. I am not responsible for your bad judgement.
Let me know if this works for others. I have tested it on my app Labelert.com and it seems to be working after I made a slight update to the unread label.
P.S. Sorry I cant post direct links yet.
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