I have tested several Google Chrome extensions and I wasn't convinced by any of them, so that's why I am sticking with Firefox + Xmarks. The native Firefox bookmark managing is pretty handy, Cmd+B and you toggle it, and searching is instantaneous. I can have my bookmarks open while I see the page on the main window (something lacking on chrome). I also like to be able to add 'separators' and I only miss that the search would also pick folders (I need to go to chrome for it). I also use Pocket, but it is a different use case for me. I need the bookmarks to keep my 'resources' about different technologies, not to keep my reading list (where I use pocket). Another alternative would be Evernote + Evernote Web Clipper. Although that could clutter your Evernote library if you use it extensively for your notes.

On JavaScript, for sure! It's not completely easy to learn, and it's also easy to get out of hand if you don't follow best practices. On the other hand, the amount of books, tutorials and resources available for learning is pretty decent, so with a bit of work, everything is possible! Take a look at this post about learning resources .

Weeks ago I wrote about this issue on Eventbrite's Engineering Blog, take a look: https://engineering.eventbrite.com/d3-js-resources-to-level-up/ I tried to taylor it a bit depending on your current skills on D3. I would also love to get some feedback about the post, feel free to suggest more resources!

I don't think there is a right answer to this question without talking about the scope of the project, the in-house expertise available, the level of customization required and many more parameters.