Is it safe to paste your Roblox cookie?
Pasting your Roblox cookie is not safe unless you completely trust where it is going. Your .ROBLOSECURITY cookie is your entire logged-in session. A valid copy lets someone act as you, often past two-step verification, without ever needing your password. Any tool that asks you to paste it is asking for the keys to your account, so the safest answer is simple: don't, and use a tool that never requires it.
That is exactly the standard the BetterBLOX Roblox account manager is built to. It signs you in through the normal Roblox login window, so you never have to paste a session token to add an account. A paste box is still there for the times a captcha or 2FA blocks that window, and what it stores is encrypted for your device and OS user.
Why the cookie is so sensitive
Passwords can be protected by two-step verification; a session cookie is different. It represents a login that already happened, so possessing a valid one usually skips the password and the second factor entirely. That is the whole reason cookie-logger scams exist. They do not need to phish your password if they can get you to hand over the cookie directly. Treat it like a live key to your account, because that is what it is. Our account-safety policy is built around never asking for it.
If you have already pasted one
If you pasted your cookie somewhere you are not sure about, rotate it: log out of Roblox everywhere and change your password, which invalidates existing sessions. Turn on two-step verification if it is off. Then switch to a tool that does not need the cookie in the first place, so you never have to think about this again.
The safer way to manage accounts
You do not have to choose between convenience and safety. A manager that launches the official client and adds each account through Roblox’s own sign-in window gives you the same one-click switching without ever asking you to dig a cookie out of devtools. That is the design worth insisting on: if a tool only works when you hand it your .ROBLOSECURITY, look for one that doesn't.