It is great to see it running on your device! Looking at Screenshot_20260906_03
4502.jpg and Screenshot_20260906_034509.jpg, the scaling and layout worked out
perfectly for the mobile Chromium viewport.
To intercept the native console methods (log, error, warn, info) so they pipe
directly into your custom REPL overlay, we just need to temporarily override
the global console object.
We will wrap the original methods so they still fire natively (in case you
ever do plug into a desktop for USB debugging), but they will also format and
print their arguments to our #repl-output div.
You can paste this block of code completely at the bottom of your <script>
tag, right before the closing </script> in your windows.html file.
Add this to the bottom of your script:
    /* =========================================
       5. CONSOLE INTERCEPTOR
       ========================================= */
    (function interceptConsole() {
      // 1. Store the original native browser methods
      const originalLog = console.log;
      const originalError = console.error;
      const originalWarn = console.warn;
      const originalInfo = console.info;

      // 2. Helper to print to our REPL
      function printToREPL(prefix, args, color) {
        // Convert all arguments to strings using our existing formatOutput
function
        const msg = Array.from(args).map(arg => formatOutput(arg)).join(' ');
        
        // Append to the REPL output
        if (typeof replOutput !== 'undefined' && replOutput) {
          replOutput.innerHTML += `
<span style="color:${color}">[${prefix}] ${msg}</span>`;
          replOutput.scrollTop = replOutput.scrollHeight; // auto-scroll
        }
      }

      // 3. Override the global console methods
      console.log = function(...args) {
        originalLog.apply(console, args); // Still log to native dev tools
        printToREPL('log', args, '#cecece'); // Light gray
      };

      console.error = function(...args) {
        originalError.apply(console, args);
        printToREPL('error', args, '#f48771'); // Red
      };

      console.warn = function(...args) {
        originalWarn.apply(console, args);
        printToREPL('warn', args, '#d7ba7d'); // Yellow
      };

      console.info = function(...args) {
        originalInfo.apply(console, args);
        printToREPL('info', args, '#569cd6'); // Blue
      };
    })();

How to test it
Once you add this, reload the page on your phone, open the REPL, and try
triggering these in your app code or typing them directly into your new
prompt:
 * console.log("Hello", { user: "Admin" })
 * console.error("Failed to load module")
 * console.warn("High memory usage")
All background events happening in your hidden virtual displays that fire a
console.log will now immediately appear in your REPL overlay, giving you full
visibility of your app's state directly on the touchscreen.