This is as a working version of the part of Optimoz Tweaks that I used. The sidebar auto open and close when the mouse touches the left side of the browser window. I rewrote the preference page to be inline and the way the preferences are read/written by the extension. I removed 'eval's and 'setTimeout's that generally aren't allowed in extensions for security reasons. I wrapped the everything in the extension in a variable and rewrote the way many functions are called (so they could be wrapped.) I eliminated several functions that were only called once or twice and were only one or two lines long. Replaces all 'var's with 'let's. I fixed the hand icon that can hold the sidebar open regardless of mouse position. Probably more too, but that's all I can remember. This extension does constantly check mouse position which can theoretically be a performance hit. I've never even seen 1% CPU usage when moving the mouse though.