Fix dictionary image support (#1526)

* Fix content security policy for images

* Add createBlobFromBase64Content to MediaUtil

* Update MediaLoader to use MediaUtil

* Use blob URLs when importing dictionaries

* Update VM's URL to support createObjectURL and revokeObjectURL

* Fix test

1 files changed, 3 insertions, 1 deletions

diff --git a/ext/js/language/dictionary-importer.js b/ext/js/language/dictionary-importer.js
index b4429315..888d19b0 100644
--- a/ext/js/language/dictionary-importer.js
+++ b/ext/js/language/dictionary-importer.js
@@ -400,7 +400,9 @@ class DictionaryImporter {
                 eventListeners.removeAllEventListeners();
                 reject(new Error('Image failed to load'));
             }, false);
-            image.src = `data:${mediaType};base64,${content}`;
+            const blob = MediaUtil.createBlobFromBase64Content(content, mediaType);
+            const url = URL.createObjectURL(blob);
+            image.src = url;
         });
     }
 }