Crowning of Noveritsch
When Noveritsch was crowned king of Finland, he immeidiately declared war on Sweden, to claim some stolen towns. After this, Russia and Kamtchatka announced support for Sweden, with Russia saying that despite Sweden being inactive, they have active allies.
During the War
Indirect involvement of Denmark
Despite Denmark and Finland not being allies, Denmark stole a Swedish town, Gothenburg. This meant that Denmark indirectly supported Finland. However, Denmark doesn't have hostilities against Sweden. Meaning, Denmark is, and isn't in the war, leaving it in a intriguing spot.
End of War
During the war, it became chaotic. Eventually the Swedish side decided that they'll be active again, and started to work on a treaty with Finland. Eventually they reached an agreement on a border, and the ceding of Visby to Finland. In the end it was considered a de facto loss for Sweden as they lost two towns, however since there was a treaty and both sides ended the war it can also be called unconclusive.