According to Gatsby (Blogger employee) :
We did this because we had seen a lot of data corruption due to 'badAnd, as I only create blogger templates based on the simplest blogger theme - Minima, so these templates have simple and correct coding and upload without any errors.
templates,' and we are trying to stave off some of these issues pre-emptively.
Now we realize that this has caused some inconvenience to folks, so we
are re-thinking our decision and will post an update on that shortly.
In the meantime, I thought I'd pass along a workaround that should
work for most people.
Here's a new Blogger Template - Dark Wooden Texture
Instructions: How to change Blogger Templates
If you want to improve it further, and make it more friendly, then see these blogger tips and tricks