If a token you want to bridge isn't officially supported yet via Superbridge, there's two main ways this token could be enabled for bridging.
Custom token imports
Superbridge offers permissionless token bridging, so if the token is already deployed onto a rollup you can simply "import" it for bridging.
All you need to do is paste the token address into the token search modal, and import the token.
Note that you must paste the address of the token on the rollup. From this Superbridge can query any relevant bridge contracts and the corresponding settlement chain token address. Simply pasting in the settlement chain ERC20 token address won't be enough.
If you need help deploying a token to a rollup, you can checkout our friends at Supermigrate or contact the team behind the rollup.
Token list
Superbridge sources many tokens from the official Optimism token list. Once tokens are merged into this list they should start feeding into Superbridge within the hour.
I still need help
If your token isn't compatible with the native bridge, it could still be supported by Superbridge! Reach out to us via the little support icon in the bottom right of this page and we can have a chat.