As explained in How did Alaska "change its primary system recently" and was it "to dilute the possibility of a conservative or Trump-inspired challenger"?:
Alaska Ballot Measure 2 made two big changes to elections, both of which are expected to reduce the power of the main parties:
Party-run primary elections are replaced with non-partisan primary elections (sometimes called Jungle primaries). In a non-partisan primary, all candidates, regardless of party, run against each other in a primary election and the top vote-getters move on to the general election. Usually, in a non-partisan primary, the top-two candidates move on, but in Alaska's new system the top four move forward. This is because of the second change instituted by Ballot Measure 2:
The normal first-past-the-post system has been replaced with ranked choice voting among the top-4 candidates from the primary. Instead of casting a single vote for a candidate, voters rank their candidates. If no one receives a majority of the votes, the last place candidate is removed and their voters are assigned to the other candidates based on their second choices. This continues until one candidate has a majority.
But... why didn't they also introduce ranked voting for the primary? It seems like that it would be just as beneficial there as it is for the general election. Have there been any discussions of this question in the legislature of Alaska?