I need to commission a plugin (free or paid, up to you), perhaps called MoreOxygen, that allows me to change the default amount of oxygen in diving tanks (crafted w/ configured amount, crate-looted tanks would have the configured amount, and all tanks could be repaired/refilled to the configured amount) as well as the newly introduced oxygen amounts provided inside submarines. These amounts would need to be controlled from the plugin's config and would be available to all players with the necessary custom permission (moreoxygen.use, for example). Ideally, there would be separate configurable values for diving tank, solo sub, and duo sub. If interested, please reply or DM me to discuss further.

Submarine oxygen consumption rate can be changed with the basesubmarine.oxygenminutes convar. It defaults to 10 minutes. If changed, the max time still shows as 10 min, but it reduces more quickly or more slowly.

WhiteThunder

Submarine oxygen consumption rate can be changed with the basesubmarine.oxygenminutes convar. It defaults to 10 minutes. If changed, the max time still shows as 10 min, but it reduces more quickly or more slowly.

Thanks for the tip. I've modified that convar to affect the submarines and reported the HUD not updating to reflect the modified total minutes to FP.