Editora 0.20.0. Archived, so links from that release keep working. Read the 0.24.0 page →
LSP: Go to Definition in Split
lsp.gotoDefinitionInSplit Open the definition of the symbol at the cursor in a split beside the current file, so the call and the thing called are on screen together.
How to run it
Open the command palette (M-x in the Emacs keymap) and search for LSP: Go to Definition in Split, then press Enter. It has no default keybinding, but you can bind one in Settings → Keymaps.