Editora 0.9.10. Archived, so links from that release keep working. Read the 0.18.3 page →
View: Toggle HTTP Client Support
view.toggleHttpClient Enable or disable the HTTP client for .http/.rest files.
How to run it
Open the command palette (M-x in the Emacs keymap) and search for View: Toggle HTTP Client Support, then press Enter. It has no default keybinding, but you can bind one in Settings → Keymaps.