Any tool becomes useful when we are instructed how to use it.

Of course we don't expect a long documentation for a tiny piece of code like this. But to provide the basic information is mandatory.

It's great to tell the users that "With Snap Links Plus you can open multiple links in to new tabs by drawing a selection rectangle. Etc. Etc." But it's indecent not to tell them HOW !!!
HOW TO DRAW THE SELECTION??? It doesn't work by simple drag and drop, nor by Ctrl+drag and drop or any other modifier + drag and drop. And even if it would work, it isn't tell where we would find the promised multitude of options: in the context menu? in a context menu automatically opened?

It is said that a picture is worth a thousand words. Wrong!!! In this matter ten words are worth a thousand pictures. The two demonstrative pictures the developer added don't demonstrate anything.

it is a cheap excuse to tell that this add-on "is free and open-source". Trying unsuccessfully to use it did cost me a lot of time and frustration. And it is impolite to tell the users "Please report any issues or feature requests to our Issue Tracker." in other words: I don't care what are you saying here. The Issue Tracker is for technical issues. And it's even not an issue with the program, but with the documentation.