The main issues Google detected on my posts are: the post is wider than the screen and clickable elements are too close to each other.

This you can see when you click on the mobile usability.

If you see this notifying Google about your new post, do the following:

1 Go back to your post

2 make changes Google wants you to do:

I.e. Make the fonts bigger if there is a complaint they are too small. This was my first challenge. But after I changed the fonts and got another problem: the post is wider than the screen. Wooo. Make fonts smaller.

If the challenge is clickable elements are too close, enhance the spaces - sometimes especially at the end of the post the clickable elements are surely crowded - as on my website and it seems not possible. Then press return for one more empty space. Check back with GSC.