Are browser extensions for the Roblox website safe to use?

The two everyone runs are BTRoblox and RoPro, and they've been around for years without trouble. BTRoblox is open source so people have actually read it. The rule for anything else: an extension can read every page you're on, which includes the login cookie, so a random one promising free robux or a trade bot is exactly how accounts get stolen. Website extensions aren't against the rules, anything touching the game client is.