Thanks for the advice! Please forgive me for the delay in replying.
I have confirmed that the groundwork has been cleaned up thanks to your and others' help to me!

After your suggestion, I have started to remember to rectangle with the Q key on many occasions.
In January 2024, another proficient mapper (osm.org/user/Hokkosha) doing crisis mapping gave similar advice (“Don't forget the Q key!”) ) to new mappers, and I suspect that the latest maps sourced from photogrammetry in the Noto Peninsula are now very easy for human eyes to see, even with machine discrimination for accessibility purposes.

Keep up the good work.

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