> How about a treesitter-based editor extension that converts between begin/end and {/}, as if they were ligatures? Actually this might not even need treesitter

> How about a treesitter-based editor extension that converts between begin/end and {/}, as if they were ligatures? Actually this might not even need treesitter. Neovim has the conceal feature, which can convert Treesitter nodes into a single symbol, but not the other way around unfortunately.