TagSpaces is distributed with a build-in viewer for `.url`, `.website` and `.desktop` files. These file types are used by various operating system for saving bookmarks to web sites. This feature is basically enabling you to use TagSpaces as a bookmark manager. `.url` files can be created for example in Windows by dragging and dropping over the desktop a website from your browser. `.desktop` files are the alternative to the `.url` files in Ubuntu.
Alternatively you can use the TagSpaces browser extensions for Chrome and Firefox to create bookmarks in the supported format. In addition to saving the url and the data when the bookmark is created, both browser extensions are taking a screenshot of the current visible part of the web page. This screenshot is used later for creating the thumbnail of the bookmark in TagSpaces.