updated known issues

README.MD

@@ -59,7 +59,7 @@ See https://addons.mozilla.org/en-US/firefox/addon/single-file/statistics/?last=
 
 ## Known Issues
 - All browsers:
-  - For security reasons, you cannot save pages hosted on https://chrome.google.com, https://addons.mozilla.org and some other Mozilla domains. When this happens, 🚫 is displayed on top of the SingleFile icon.
+  - For security reasons, you cannot save pages hosted on https://chrome.google.com, https://addons.mozilla.org and some other Mozilla domains. When this happens, 🛇 is displayed on top of the SingleFile icon.
   - The last saved path cannot be remembered by default. To circumvent this limitation, disable the option "Misc > Save pages in background".
   - The following characters are replaced with _ in filenames: ~, \\, ?, %, *, :, |, ", <, >  
 - Chrome: