SPACE to walk through all grid squares

[MarcusJT]

Navigating around using up/down/left/right requires attention to be paid to the grid map and/or arrows that appear.

What's missing is a way to easily navigate/walk through all the grid squares in a linear fashion - with presentations pressing SPACE is the established way to do it and should be applied here, walking through all the grid squares one by one (i.e. left-to-right, top-to-bottom).

[mknecht]

Yeah, that makes total sense for presentations, where you have aggregating/introductory slides, and then dive into details.

However, I wrote this for articles with bigger discussions (read: big footnotes). There, you follow a train of thought and do not want to get side-tracked — unless you actually care for a particular side-discussion and accept leaving the article's flow. Therefore, the default scrolling is downwards only.

Thanks for the feedback!