This sounds like a really mundane topic for an article, but you'll be glad it's here. This took me hours to figure out.
While designing a Word Template for a modified SOP Blank Invoice report, I needed a new column so I added one in the grid.
Now the row is too tall, I can't make it shorter. I was able to see the issue by selecting 'cell > select row'
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Notice the date column...
After quite a while, I figured it out