Table of contents is the feature that, in my opinion, ought to be implemented as a part of the web browser instead of within the document (I was told that Dillo

Table of contents is the feature that, in my opinion, ought to be implemented as a part of the web browser instead of within the document (I was told that Dillo apparently did at one time (but no longer does, although I suggested to them to add it again), and it is commonly implemented in Gemini browsers, though). This would also be true of page progress, linkable headings (the document author would need to give it a ID, although the browser should then handle the rest), link preview, and markers for external links. This should also be true of fonts and colours, too; the document author should not need to specify them. Some of the other things they mention, are things that would be helpful for the document author to handle, though.