Online marking of errors

[clecap]

We need a possibility to mark typos during the presentation of a wiki pages as a slide.

One sees a typo and is not in the position of fixing it immediately but wants to put a marker for later. Marking the block or marking the specific position even.

We need it not only in a "show" endpoint but also in a normal view endpoint.

A possibility of adding a remark / annotation would be helpful as well