Hypothes.is is a really great tool to help to annotate almost all content on internet, however, it does not support firefox that well. The firefox addon is under development for ages. The alternative way to use it is though bookmarklet, which is simple enough, but you have to click the bookmarklet everytime when you open a web page. It is annoying and not efficient. The codes above are the source codes for the plugin, in the plugin codes, there are also a black list to exclude the websites, such as WordPress admin dashboard, local websites, google search results and youtube. Howto go to GreasyFork search Hypothesis Assitant or simply open this url Greasy Fork Hypothesis Assitant and install it for GreasyMonkey (or other scripts manager) https://github.com/diegodlh/unofficial-hypothesis-extension the official firefox extension was released. Alternative Memex Bookmarking Memex Bookmarking add-on is a hypothesis alternative, it is a browser add-on with free and pro plan for users. References Greasy Fork Hypothesis Assitant Source Code Hypothesis web annotation in Firefox Hypothesis wordpress memex bookmark Leave your comments here if you have any questions.