is to require that any attempt to fire or interfere with Bob Mueller’s office result in immediate review by the full Supreme Court, and pending the decision of the court, any such action shall have no effect.
If the Republicans refuse to support such a measure, then everyone can see they are hypocrites, who have no desire for an impartial investigation to be completed. If they pass it, then Trump could veto it, and personally shutdown the government to preserve his option to fire Mueller, which he denies planning to do.
I don’t think there any issue more critical than this one. All of the others are important, but this is the only one which is could truly avert a constitutional crisis.