Go.appsilon.com has been moved our (Yourls service)[https://yourls.org/] hosted on AWS Lighsail. URL shortening is available under https://go.appsilon.com/admin (credentials available in 1password team vault). User readme moved to Outline: https://appsilon.getoutline.com/doc/tools-VNEKJXIy09
Appsilon URL tool: https://go.appsilon.com/link/
Just add new directory with proper index.html file. You can choose between url masking (original page is in an iframe) or visible redirection.
Be aware that some websites prevent from displaying them inside iframe. When you see blank page check browser console for the following error:
Refused to display 'https://app.asana.com/0/595107366583797/list' in a frame because it set 'X-Frame-Options' to 'sameorigin'