fix(browser-check): disable es2020 syntax probes

Author: cst8t

public/browser-check.js

@@ -7,7 +7,6 @@
  *
  * Required features (determined from caniuse-lite against the app's CSS/JS):
  *   CSS Grid, CSS Custom Properties, position:sticky (or -webkit-sticky)
- *   ES2020 syntax used by the bundle, currently optional chaining and nullish coalescing
  *
  * Chromium version is still checked via UA for WebView2 on Windows, where the
  * version string is accurate and ES module support (Chrome 61+) is the constraint.
@@ -16,15 +15,6 @@
   var unsupported = false;
   var body = '';
 
-  function canParse(source) {
-    try {
-      new Function(source);
-      return true;
-    } catch (e) {
-      return false;
-    }
-  }
-
   /* CSS feature detection -------------------------------------------------- */
   if (typeof CSS === 'undefined' || !CSS.supports) {
     unsupported = true;
@@ -42,15 +32,30 @@
     }
   }
 
-  if (!unsupported) {
-    var missingJs = [];
-    if (!canParse('var value = ({ a: 1 })?.a;')) missingJs.push('optional chaining');
-    if (!canParse('var value = null ?? 1;')) missingJs.push('nullish coalescing');
-    if (missingJs.length > 0) {
-      unsupported = true;
-      body = 'Missing required JavaScript features: <strong style="color:#e2e4eb;">' + missingJs.join(', ') + '</strong>.';
-    }
-  }
+  /*
+   * ES2020 syntax probes are disabled for now. Tauri's CSP can block
+   * Function() even when the webview supports the syntax, which makes this
+   * check report a false unsupported browser.
+   *
+   * function canParse(source) {
+   *   try {
+   *     new Function(source);
+   *     return true;
+   *   } catch (e) {
+   *     return false;
+   *   }
+   * }
+   *
+   * if (!unsupported) {
+   *   var missingJs = [];
+   *   if (!canParse('var value = ({ a: 1 })?.a;')) missingJs.push('optional chaining');
+   *   if (!canParse('var value = null ?? 1;')) missingJs.push('nullish coalescing');
+   *   if (missingJs.length > 0) {
+   *     unsupported = true;
+   *     body = 'Missing required JavaScript features: <strong style="color:#e2e4eb;">' + missingJs.join(', ') + '</strong>.';
+   *   }
+   * }
+   */
 
   /* Chromium version check (WebView2 on Windows only) ---------------------- */
   if (!unsupported) {