https://arstechnica.com/gadgets/2021/03/microsoft-adds-startup-boost-sleeping-tabs-to-edge-build-89/

This week, Microsoft announced several more features trickling down to Edge Stable from its Beta insider channel. These features include Startup Boost, Sleeping Tabs, Vertical Tabs, and a more navigable History dialog. The company also announced some welcome interface tweaks to Bing—which Microsoft insists on categorizing as Edge features, but these items seem to apply equally to Bing in any browser so far.

If you're not familiar with Microsoft Edge's release and download system, there are three Insider channels (Canary, Dev, and Beta) that represent daily, weekly, and six-weekly updates in increasing order of stability. New features debut there before eventually making their way into Stable, where normal users will encounter them.