diff --git a/platform/common/vapi-background.js b/platform/common/vapi-background.js
index d292341ec..ff6ffd1e1 100644
--- a/platform/common/vapi-background.js
+++ b/platform/common/vapi-background.js
@@ -48,7 +48,7 @@ vAPI.supportsUserStylesheets = vAPI.webextFlavor.soup.has('user_stylesheet');
 vAPI.app = {
     name: manifest.name.replace(/ dev\w+ build/, ''),
     version: (( ) => {
-        let version = manifest.version;
+        let version = manifest.version_name || manifest.version;
         const match = /(\d+\.\d+\.\d+)(?:\.(\d+))?/.exec(version);
         if ( match && match[2] ) {
             const v = parseInt(match[2], 10);
diff --git a/platform/common/vapi-common.js b/platform/common/vapi-common.js
index 1402f4d7a..65e0c93c5 100644
--- a/platform/common/vapi-common.js
+++ b/platform/common/vapi-common.js
@@ -166,7 +166,9 @@ vAPI.webextFlavor = {
     soup.add('ipaddress');
 
     // Whether this is a dev build.
-    if ( /^\d+\.\d+\.\d+\D/.test(browser.runtime.getManifest().version) ) {
+    const manifest = browser.runtime.getManifest();
+    const version = manifest.version_name || manifest.version;
+    if ( /^\d+\.\d+\.\d+\D/.test(version) ) {
         soup.add('devbuild');
     }