What Leon says is true. But in this case, the same would be true of Moodle 3.9 and 3.8 versions too. The marketing blocks use a custom admin setting that has 'issues', I'm not that happy with the code (that I did not create), so in the long term, it would be better to replace that area with a block region that displays blocks horizontally and makes them all the same height - as I've done in my other themes - just something I've not gotten around to. Having said that, I'm not sure if I will in Adaptable, all depends on circumstances.
Using blocks is far better in that you get all the benefits of ones like the HTML block that do all of the file storage etc. for you.