Here are some userscripts that can be used to modify the behavior of websites. You will need an extension that loads userscripts to install these scripts. I recommend the extension ViolentMonkey (Chrome/Firefox)
CS1XD3 Better Editor v0.4
makes the editor better probably. originally written as a devtools patch CS1XD3 Dark Theme v1.2
introduces a dark mode CS1XD3 Freeze Patch v1.2
prevents freezing of the website CS1XD3 Editor VIM Mode v0.2
adds vim mode to the editor Avenue Auto Login v1.0
Automatically logs in when visiting Avenue to save time Avenue Inactivity Disabler v1.0
Disables inactivity signout Avenue Title Changer v1.0
Changes titles such as "(4) The Relational ..." to "4 - The Relational ..." CalcCheck Sanity Tracker v1.0
Totals the minutes, hours, days, weeks, or months spent trying to debug issues in CalcChck. CalcCheck Dark Theme v1.6
Adds a dark theme and other style improvements to CalcCheck Mosaic Auto Login v1.5
Automatically logs in when visiting Mosaic to save time CS1XD3 Freeze Patch
v1.2prevents freezing of the websiteNo instructions provided.