Tax treaties generally reduce the U.S. taxes of residents of foreign countries as determined under the applicable treaties. With certain exceptions, they do not reduce the U.S. taxes of U.S. citizens or U.S. treaty residents. U.S. citizens and U.S. treaty residents are subject to U.S. income tax on their worldwide income.  So report it as income and claim FTC (although this might require filing a Canadian return, because the tax withheld may not be tax owed).

IRS in its latest update said they have only 19,000 returns from 2019 left in the processing pipeline.  I don't believe them.