In order to change the account number tag without Nitro, change the username to an username that has an identical numerical tag. For instance, if there are two users bill#8000 and jane#9888, then if bill#8000 changes the username to jane, the numerical tag 8000 will be randomly rolled again.

In order to run multiple Discord instances at the same time whilst logging into different accounts, create a shortcut from the Discord.exe binary and adjust the Target to include the –multi-instance switch:

C:\Users\...\AppData\Local\Discord\app-1.0.9013\Discord.exe --multi-instance

Discord does not benefit from a feature that would allow one to delete all message history from a chat, but this can be accomplished via Greasemonkey and Undiscord that essentially perform some looped automation where all messages are retrieved and then manually deleted as if the user were to delete the messages on their own by browsing the message history.

The procedure using these two tools is easy, it just requires installing Greasemonkey or similar, and then installing the Undiscord script. After that, browsing to a Discord server or chat will reveal a garbage can on the top upper right of the interface that, one clicked, will reveal an interface allowing the user to delete all past messages.