Chrome extension to remove Bob from popping up in Canvas.
The important folder you will need on your computer is "no-bob" that contains background.js, content.js, and manifest.json. Copy that somewhere helpful.
In Chrome, go to chrome://extensions/ and make sure "Developer Mode" is enabled in the upper-right corner. Then click the "Load unpacked" button on the top left and select the "no-bob" folder.
After loading the extension, which will be called "Canvas Chatbox Dismissal 1.0" in Chrome, there is a circular arrow button on the bottom-right corner of the extension box. Click that.
Hopefully, every time you go to Canvas now Bob will close itself automatically upon popping up! If it doesn't...
This extension seems to have trouble running alongside some ad blocker extensions. I had to set AdBlock to remain paused on my Canvas page for every visit, and disable uBlock Origin for the same site. Turning those off made it work. Good luck!