Minnesota resident working in California for most of the year, employer withheld and reported to CA until just recently

[TomD8]

Minnesota can tax 100% of a Minnesota resident's income, regardless of where it was earned.  

As explained before, CA taxes non-residents only on CA-source income.  Again, the W-2 income of a non-resident of CA who performed no work inside CA is not CA-source income.  Work income is "sourced" where the work is actually performed.

"Temporary" vs "permanent" employment is irrelevant from a tax point of view.  The issue is where the work was actually (not virtually) performed.

At present, the only states that tax non-resident remote employees are AR, DE. NE, NY, and PA.