If I have many tabs open that I need to review and sift through and I want to put that process on hold, I use the OneTab extension that will collapse all the tabs and save all the urls as a group on the OneTab app page. You can name each group, click on a button to launch tabs for all the links in the group, etc.

Big picture though, for each project or endeavor I'm working on I create a folder in google drive with a document named journal where I journal my thoughts, ideas, meanderings on the project. I start collecting important links relevant to the project there. Over time I add more documents and folders to organize my work on the project and save/document any important resources.