For my browser it is not working my browser is firefox and nothing working in app inventor i am not able to go inside my projects and blocks are not working two.Thank you please solve this problem.Thank you.
i think you should try to use google chrome 
The http://ai2.appinventor.mit.edu/ App Inventor 2 web link is working fine at the moment for me Suhas.
A guess is an issue with your Internet provider and dsl speed. You might have a temporary slow Internet speed. Without a better description of your issue it is impossible to guess at a solution. You might try Salman's suggestion to try a different Browser. Do not use Edge which has demonstrated erratic behavior with App Inventor in the past. What happens if you try a different browser? Please let us know.
Take some screenshots of what you get, especially if you see error messages, and post them here. Also let us know
- which Firefox version,
- which operating system,
- good / bad internet connection,
- etc.
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