Terser options for bookmarklets

.terserrc.js

{
  module: false, // bookmarklets are usually classic scripts, not ESM

  parse: {
    ecma: 2020
  },

  compress: {
    ecma: 2020,
    passes: 2,
    dead_code: true,
    drop_debugger: true,
    evaluate: true,
    inline: 2,
    loops: true,
    conditionals: true,
    booleans: true,
    sequences: true,
    comparisons: true,
    reduce_funcs: true,
    reduce_vars: true,
    collapse_vars: true,
    // IMPORTANT for bookmarklets:
    toplevel: false,
    // usually keep console logs during dev; flip to true for release
    drop_console: false
  },

  mangle: {
    // IMPORTANT for bookmarklets:
    toplevel: false,
    // don't mangle property names in injected scripts
    properties: false
  },

  output: {
    ecma: 2020,
    comments: false,
    ascii_only: true,
    wrap_iife: true // keeps things self-contained (bookmarklet-friendly)
  }
}