What will you do when the Lappland Liberation Front start a guerilla war led by small units on reindeerback then?
My bet is on neo-fascist anti-Russian movements with a strength of about 3 men in the Russian Republic of Karelia that need to be crushed with 15-ish motor rifle brigades some 600 km to the West. That, or a Russian aircraft or two are "shot down". Mind you, the hybrid warfare against us has been on for years already. Just not in anywhere near the same scale as in Ukraine, and besides Armenia, we're still Russia's best neighbors. In a way.
I don't think we have problems similar to Ukraine. Corruption, money, rusting gear, lacking organization and drilling aren't issues, and nobody would consider the conflict a civil war. Manufacturing an internal conflict would be very difficult. Defense budget has been cut several times the past years but we will be seeing an increase in both it and readiness in general soon. The whole military is geared and drilled for rapid response, fighting in depth and counterattack, and escalation bit by bit just wont work after April this year when it comes possible for the Chief of Staff to mobilize 25,000 to man the armored units(which would rise the peacetime strength to about 40,000) without the need ask the parliament or even the prime minister. The so called "Yellow A2" may grab a village or two with insurgents speaking incomprehensible could-be-Finnish, but then what? They'd face a large conventional army, an air force and a cruise missile threat to deep behind the border should they let the defender have the couple of days to mobilize. And that defender would have the means to stop all naval and air traffic but submarines in the Gulf of Finland.