diff --git a/api/GPUAdapter.json b/api/GPUAdapter.json
index 076f29b45e66f4..f56e55213a4d36 100644
--- a/api/GPUAdapter.json
+++ b/api/GPUAdapter.json
@@ -128,9 +128,7 @@
               "partial_implementation": true,
               "notes": "Supported on ChromeOS, macOS, and Windows only."
             },
-            "chrome_android": {
-              "version_added": "127"
-            },
+            "chrome_android": "mirror",
             "edge": "mirror",
             "firefox": {
               "version_added": "141",
@@ -452,9 +450,7 @@
                 "partial_implementation": true,
                 "notes": "Supported on ChromeOS, macOS, and Windows only."
               },
-              "chrome_android": {
-                "version_added": "133"
-              },
+              "chrome_android": "mirror",
               "deno": {
                 "version_added": false
               },
diff --git a/api/GPUCommandEncoder.json b/api/GPUCommandEncoder.json
index cf0e98c5a8e5c8..2c1d336c4ffecc 100644
--- a/api/GPUCommandEncoder.json
+++ b/api/GPUCommandEncoder.json
@@ -127,9 +127,7 @@
                 "partial_implementation": true,
                 "notes": "Supported on ChromeOS, macOS, and Windows only."
               },
-              "chrome_android": {
-                "version_added": "121"
-              },
+              "chrome_android": "mirror",
               "deno": {
                 "version_added": false
               },
@@ -226,9 +224,7 @@
                 "partial_implementation": true,
                 "notes": "Supported on ChromeOS, macOS, and Windows only."
               },
-              "chrome_android": {
-                "version_added": "140"
-              },
+              "chrome_android": "mirror",
               "deno": {
                 "version_added": false
               },
@@ -268,9 +264,7 @@
                 "partial_implementation": true,
                 "notes": "Supported on ChromeOS, macOS, and Windows only."
               },
-              "chrome_android": {
-                "version_added": "125"
-              },
+              "chrome_android": "mirror",
               "deno": {
                 "version_added": false
               },
@@ -309,9 +303,7 @@
                 "partial_implementation": true,
                 "notes": "Supported on ChromeOS, macOS, and Windows only."
               },
-              "chrome_android": {
-                "version_added": "123"
-              },
+              "chrome_android": "mirror",
               "deno": {
                 "version_added": false
               },
@@ -351,9 +343,7 @@
                 "partial_implementation": true,
                 "notes": "Supported on ChromeOS, macOS, and Windows only."
               },
-              "chrome_android": {
-                "version_added": "121"
-              },
+              "chrome_android": "mirror",
               "deno": {
                 "version_added": false
               },
@@ -508,9 +498,7 @@
                 "partial_implementation": true,
                 "notes": "Supported on ChromeOS, macOS, and Windows only."
               },
-              "chrome_android": {
-                "version_added": "137"
-              },
+              "chrome_android": "mirror",
               "deno": {
                 "version_added": false
               },
diff --git a/api/GPUDevice.json b/api/GPUDevice.json
index 5cc8a90bbfd43e..0dced8188ca013 100644
--- a/api/GPUDevice.json
+++ b/api/GPUDevice.json
@@ -167,9 +167,7 @@
                 "partial_implementation": true,
                 "notes": "Supported on ChromeOS, macOS, and Windows only."
               },
-              "chrome_android": {
-                "version_added": "138"
-              },
+              "chrome_android": "mirror",
               "deno": {
                 "version_added": false
               },
@@ -208,9 +206,7 @@
                 "partial_implementation": true,
                 "notes": "Supported on ChromeOS, macOS, and Windows only."
               },
-              "chrome_android": {
-                "version_added": "140"
-              },
+              "chrome_android": "mirror",
               "deno": {
                 "version_added": false
               },
@@ -249,9 +245,7 @@
                 "partial_implementation": true,
                 "notes": "Supported on ChromeOS, macOS, and Windows only."
               },
-              "chrome_android": {
-                "version_added": "137"
-              },
+              "chrome_android": "mirror",
               "deno": {
                 "version_added": false
               },
@@ -801,9 +795,7 @@
                 "partial_implementation": true,
                 "notes": "Supported on ChromeOS, macOS, and Windows only."
               },
-              "chrome_android": {
-                "version_added": "135"
-              },
+              "chrome_android": "mirror",
               "deno": {
                 "version_added": false
               },
@@ -901,9 +893,7 @@
                 "partial_implementation": true,
                 "notes": "Supported on ChromeOS, macOS, and Windows only."
               },
-              "chrome_android": {
-                "version_added": "121"
-              },
+              "chrome_android": "mirror",
               "deno": {
                 "version_added": false
               },
@@ -1059,9 +1049,7 @@
                 "partial_implementation": true,
                 "notes": "Supported on ChromeOS, macOS, and Windows only."
               },
-              "chrome_android": {
-                "version_added": "130"
-              },
+              "chrome_android": "mirror",
               "deno": {
                 "version_added": false
               },
@@ -1362,9 +1350,7 @@
                 "partial_implementation": true,
                 "notes": "Supported on ChromeOS, macOS, and Windows only."
               },
-              "chrome_android": {
-                "version_added": "130"
-              },
+              "chrome_android": "mirror",
               "deno": {
                 "version_added": false
               },
@@ -1984,9 +1970,7 @@
                 "partial_implementation": true,
                 "notes": "Supported on ChromeOS, macOS, and Windows only."
               },
-              "chrome_android": {
-                "version_added": "121"
-              },
+              "chrome_android": "mirror",
               "deno": {
                 "version_added": false
               },
diff --git a/api/GPUQuerySet.json b/api/GPUQuerySet.json
index 2acf454b5187c9..3ab300baef4819 100644
--- a/api/GPUQuerySet.json
+++ b/api/GPUQuerySet.json
@@ -301,9 +301,7 @@
                 "partial_implementation": true,
                 "notes": "Supported on ChromeOS, macOS, and Windows only."
               },
-              "chrome_android": {
-                "version_added": "121"
-              },
+              "chrome_android": "mirror",
               "deno": {
                 "version_added": false
               },
diff --git a/api/GPUSupportedFeatures.json b/api/GPUSupportedFeatures.json
index 5a7dc06b04605e..b5b2c3ff4cc05a 100644
--- a/api/GPUSupportedFeatures.json
+++ b/api/GPUSupportedFeatures.json
@@ -862,9 +862,7 @@
               "partial_implementation": true,
               "notes": "Supported on ChromeOS, macOS, and Windows only."
             },
-            "chrome_android": {
-              "version_added": "142"
-            },
+            "chrome_android": "mirror",
             "deno": {
               "version_added": false
             },
@@ -904,9 +902,7 @@
               "partial_implementation": true,
               "notes": "Supported on ChromeOS, macOS, and Windows only."
             },
-            "chrome_android": {
-              "version_added": "142"
-            },
+            "chrome_android": "mirror",
             "deno": {
               "version_added": false
             },
diff --git a/api/GPUTexture.json b/api/GPUTexture.json
index 9205a57dee9670..646d4b7783f9c7 100644
--- a/api/GPUTexture.json
+++ b/api/GPUTexture.json
@@ -169,9 +169,7 @@
                 "partial_implementation": true,
                 "notes": "Supported on ChromeOS, macOS, and Windows only."
               },
-              "chrome_android": {
-                "version_added": "132"
-              },
+              "chrome_android": "mirror",
               "deno": {
                 "version_added": false
               },
diff --git a/scripts/build/mirror.test.ts b/scripts/build/mirror.test.ts
index 6a6a5a33269aba..eb09fb953fbe2f 100644
--- a/scripts/build/mirror.test.ts
+++ b/scripts/build/mirror.test.ts
@@ -7,9 +7,39 @@ import { BrowserName } from '../../types/types.js';
 import bcd from '../../index.js';
 import { InternalSupportBlock } from '../../types/index.js';
 
-import mirrorSupport from './mirror.js';
+import mirrorSupport, { isOSLimitation } from './mirror.js';
 
 describe('mirror', () => {
+  describe('isOSLimitation', () => {
+    it('returns true for OS limitation notes', () => {
+      assert.equal(
+        isOSLimitation('Supported on ChromeOS, macOS, and Windows only.'),
+        true,
+      );
+      assert.equal(isOSLimitation('Supported on macOS only.'), true);
+      assert.equal(isOSLimitation('Not supported on Windows.'), true);
+    });
+
+    it('returns false for non-OS-limitation notes', () => {
+      assert.equal(
+        isOSLimitation('This feature requires a flag to be enabled.'),
+        false,
+      );
+      assert.equal(
+        isOSLimitation('Before version 70, this method always returned true.'),
+        false,
+      );
+      assert.equal(
+        isOSLimitation('Firefox 73 added support for this thing.'),
+        false,
+      );
+    });
+
+    it('returns false for empty string', () => {
+      assert.equal(isOSLimitation(''), false);
+    });
+  });
+
   describe('default export', () => {
     describe('version numbers match expected values', () => {
       const mappings: {
@@ -189,6 +219,38 @@ describe('mirror', () => {
           notes: 'This feature is only supported in ChromeOS, macOS and Linux.',
         });
       });
+
+      it('OS-specific partial_implementation and notes are not mirrored', () => {
+        const support = {
+          chrome: {
+            version_added: '134',
+            partial_implementation: true,
+            notes: 'Supported on ChromeOS, macOS, and Windows only.',
+          },
+        };
+
+        const mirrored = mirrorSupport('chrome_android', support);
+        assert.deepEqual(mirrored, {
+          version_added: '134',
+        });
+      });
+
+      it('Non-OS-specific partial_implementation and notes are still mirrored', () => {
+        const support = {
+          chrome: {
+            version_added: '70',
+            partial_implementation: true,
+            notes: 'This feature is incomplete and may not work as expected.',
+          },
+        };
+
+        const mirrored = mirrorSupport('chrome_android', support);
+        assert.deepEqual(mirrored, {
+          version_added: '70',
+          partial_implementation: true,
+          notes: 'This feature is incomplete and may not work as expected.',
+        });
+      });
     });
 
     describe('Validations', () => {
diff --git a/scripts/build/mirror.ts b/scripts/build/mirror.ts
index dd8408c36e038e..3224e53ffc18b3 100644
--- a/scripts/build/mirror.ts
+++ b/scripts/build/mirror.ts
@@ -15,8 +15,38 @@ const { browsers } = bcd;
 
 type Notes = string | [string, string, ...string[]] | null;
 
+const OS_NOTES = [
+  'Available on macOS and Windows only.',
+  'Available only on macOS.',
+  'ChromeOS only',
+  'ChromeOS and Windows',
+  'Fully supported on Windows and Linux, no support on ChromeOS.',
+  'Linux support is not enabled by default.',
+  'Not supported on macOS.',
+  'Not supported on Windows.',
+  'Only on macOS and Windows.',
+  'Only on Windows.',
+  'Only supported on ChromeOS',
+  'Only supported on macOS.',
+  'Only supported on Windows.',
+  'Only works on macOS.',
+  'Supported on ChromeOS, macOS, and Windows only.',
+  'Supported on ChromeOS and macOS only.',
+  'Supported on macOS only.',
+  'Supported on macOS Catalina 10.15.1+, Windows, and ChromeOS. Not yet supported on Linux.',
+  'Supported on Windows only, in all contexts except for service workers.',
+  'Supported only on macOS 10.12 (Sierra) and later.',
+  'This cursor is only supported on macOS and Linux.',
+].map((s) => s.toLowerCase());
+
 /**
+ * Check if a note indicates OS-specific limitations.
+ * @param notes A single notes string from a support statement
+ * @returns True if the notes indicate OS-specific limitations
  */
+export const isOSLimitation = (notes: string): boolean => {
+  return OS_NOTES.includes(notes.toLowerCase());
+};
 
 const matchingSafariVersions = new Map([
   ['1', '1'],
@@ -215,6 +245,30 @@ export const bumpSupport = (
 
   const newData: SimpleSupportStatement = copyStatement(sourceData);
 
+  if (
+    browsers[sourceBrowser].type === 'desktop' &&
+    browsers[destination].type === 'mobile' &&
+    sourceData.partial_implementation
+  ) {
+    const notes = Array.isArray(sourceData.notes)
+      ? sourceData.notes
+      : sourceData.notes
+        ? [sourceData.notes]
+        : [];
+    const [firstNote, secondNote, ...otherNotes] = notes.filter(
+      (notes) => !isOSLimitation(notes),
+    );
+    if (!firstNote) {
+      // Ignore OS limitation.
+      delete newData.partial_implementation;
+      delete newData.notes;
+    } else if (!secondNote) {
+      newData.notes = firstNote;
+    } else {
+      newData.notes = [firstNote, secondNote, ...otherNotes];
+    }
+  }
+
   if (!browsers[destination].accepts_flags && newData.flags) {
     // Remove flag data if the target browser doesn't accept flags
     return { version_added: false };
@@ -254,7 +308,8 @@ export const bumpSupport = (
     return { version_added: false };
   }
 
-  if (sourceData.notes) {
+  // Only process notes if they weren't already removed (e.g., for OS-specific limitations)
+  if (sourceData.notes && newData.notes !== undefined) {
     const sourceBrowserName =
       sourceBrowser === 'chrome'
         ? '(Google )?Chrome'