<tldr> element to provide a list of quick facts about the contents of a topic or chapter. Give your readers some basic info to start using and exploring the feature on their own without having to read into the detailed description. For example, you can specify the main shortcut, command, action, or the location of the settings.
A topic or chapter can have only one TL;DR block. Try not to overuse them: keep facts as brief as possible and do not add more than three in one TL;DR block.