STABLE version -- 5.1.1130.129

[tamer]

last 3 versions of extension Checker Plus for Gmail™ can't be added to CentBrowser anymore!!! can't add favorite extension to Cent, in updated browsers no any problems!!!
https://chromewebstore.google.com/detail/checker-plus-for-gmail/oeopbcgkkoapgobdbedcemjljbihmemj

error screen https://i.imgur.com/7KMtvXV.png

1. Download crx
   
2. Rename it to zip and unpack
   
3. Open manifest.json and remove "?source=sidepanel" on line 81
   
4. Load as unpacked extension
   
5. Voila!
   

Code:

    "side_panel": {
        "default_path": "popup.html"
    },