Editora 0.10.0. Archived, so links from that release keep working. Read the 0.18.5 page →
Buffer: Close Tabs to the Left
buffer.closeLeft Close all tabs to the left of the current one.
How to run it
Open the command palette (M-x in the Emacs keymap) and search for Buffer: Close Tabs to the Left, then press Enter. It has no default keybinding, but you can bind one in Settings → Keymaps.