Text editor margin should be zero (or one)

[yoshikiohshima]

When editing code, and trying to place the cursor at the beginning of line, it is hard to see whether the cursor is at the very beginning or after one space. This is a screenshot when the cursor is at the beginning:

this is after one space:

and this is how it'd look in emacs:

I am not advocating to go with a block cursor, but if the left margin is just narrow (and the cursor may have to be a bit thicker), there would be less confusion.

[JensLincke]

seems to be in the internal CSS of CodeMirror and not easy to adjust