Ignore errors when trying to embed images due to unsolvable CORS errors and misc

src/gh_comments.rs

@@ -194,7 +194,7 @@ pub async fn gh_comments(
           details.open = false;
         }});
       }});
-      document.getElementById('gh-comments-reverse-toc-order-btn').addEventListener('click', () => {{
+      document.getElementById('gh-comments-reverse-toc-order-btn')?.addEventListener('click', () => {{
         var tocList = document.getElementById('toc-list');
         for (var i = 1; i < tocList.childNodes.length; i++) {{
           tocList.insertBefore(tocList.childNodes[i], tocList.firstChild);

src/gh_comments/self_contained.js

@@ -8,7 +8,11 @@ document.addEventListener('DOMContentLoaded', function() {
       triggerUserDownload(htmlContent, `gh-comments-${ISSUE_ID}-export-${new Date().toISOString().slice(0,10)}.html`);
     } catch (e) {
       console.log(e);
-      alert(`Error: ${e.message}`);
+      if (e instanceof Error) {
+        alert(`Unable to export the comments: ${e}`);
+      } else {
+        alert(`Unable to export the comments. See the console for more details.`);
+      }
     }
   });
 });
@@ -83,7 +87,13 @@ async function inlineImages(doc) {
         canvas.getContext('2d').drawImage(tempImg, 0, 0, canvas.width, canvas.height);
         resolve(canvas.toDataURL('image/png'));
       };
-      tempImg.onerror = reject;
+      tempImg.onerror = (event) => {
+        // We got an error, probably a CORS rejection (happens with user images on GitHub), but we
+        // can't be certain. We only get an event, not an error.
+        //
+        // Anyway, let's ignore this error and use the initial source.
+        resolve(src);
+      };
       tempImg.src = src;
     });
   }));