How can I use a cookie injector?

Regarding the cookie injector - You can directly set the cookies with the [removed]s="..." command in your browser console.

Cookie Name | Value

acct         |  t=7c6483ddcd99eb112c060ecbe0543e86&s=080f651e3fcca17df3a47c2cecfcb880
To set it, you can use the [removed]s="{COOKIE_NAME}={VALUE}" command. You need to repeat this command for any cookie you want to set.
I just need to refresh the page, and the cookie will authenticate me.
I am logged in
Here, the Storage tab shows the cookies that have been set.

Note that other security controls may be put in place to prevent cookie theft, like checking other information associated with the user. (Browser, IP, etc.) It is the case here, I couldn't do much before being deauthenticated.