Apart from using gradient areas to switch children, you can also use the "visit next" feature that allows reading all the comments just by scrolling and using the button at the bottom. If the button is visible, it will find the closest level with unread siblings and switch to the next.

You can also use filtering when the tree of comments is not fully shown based on a criteria. Different parameters for this feature are available by clicking the "tools" link. When the "Show" button is clicked, the tree displays all the comments that fit the criteria in full while also showing the ancestors of these comments collapsed and shaded. This way, it is still a tree, and you can always check the parent/ancestor context by reading these secondary comments. The filters are mostly self-explanatory; from my experience, the "posted in last" filter is especially useful if you want to read the newest comments in an active discussion.

You can also use a URL parameter to navigate directly to a comment (e.g., /?id=40623654). This will traverse the tree up to the root story, allowing you to view the comment in its full context. An additional feature of this is the ability to save the comment as a bookmark, showing the comment along with its ancestors. The script also updates the URL during navigation, so when the page is reloaded, you will return approximately to the last item you were reading.

The underline above the comment text appears only at the "current" level, where the most recent switch was made, either by keyboard navigation or by clicking/tapping the text. The selection serves several purposes: it helps you orient yourself, especially when the switch significantly changes the layout and it’s not obvious where you are reading. The current level also updates the URL, so when the page is reloaded, the selected comment will be in focus. Additionally, for the "authors" tool/show feature, the selected comment automatically highlights the corresponding item in the dropdown box, allowing you to easily view comments from that author.

On devices with a full keyboard, you can navigate comments using Ctrl + arrow key presses. The vertical arrows (Up/Down) move between nodes along the path (from child to parent and vice versa), while the horizontal arrows switch between children. The "Space" key works as a "visit next" action

Technical details

• The script uses both Algolia HN API and the official HN API on the client side. The official api is currently needed just for traversing from an arbitrary HN item to its story ancestor. Early version worked with the official API only and the traces of this still exist in the source file
• The script is a single Html/Js/Css file that implements the full logic on the client side. It can even be saved and run locally.
• The idea was first implemented for desktop, and I had plans to implement it for the web. The first working prototype was mostly vibe-coded, after this phase, manually fine-tuned and coded

Share you thoughts/report your bugs at loclocationiddestinationfor at gmail dot com