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Changes between Initial Version and Version 1 of Ticket #31253, comment 6

initial	v1
5	5	An argument against doing this is that the theme might not set this on the front end and surprise the user. I still think we should do this because
6	6
7		1) most themes do force the image to fit on the front end and forget to do this in the editor (even our default themes ~~sinc~~e [31849]),
	7	1) most themes do force the image to fit on the front end and forget to do this in the editor (even our default themes before [31849]),
8	8	2) it's a really bad writing experience,
9	9	3) the theme does not need to provide any styles, so the defaults should be good, and