Installation vom Web kann nicht geladen werden
From Joomla! Documentation
The "Install from Web" being one of the four installation methods of extensions in the Extension Installer of Joomla is experiencing couple of issues preventing a correct loading of the "Install from Web" You might experience one of the following options.
- Upon enabling the plugin in the plugin manager, it just keeps spinning the "Loading" icon. After clicking on a different tab and coming back to the "Install from Web" you will receive an Error Message that says:
Can't connect to the Joomla! server. Please try again later.
- Depending on the server environment and it's connections the tab might show up correctly but one is not possible to select any extension and will receive an Error Message that says:
Cannot find any extensions for your version of Joomla. Please try a different search word or another category.
These issues have been identified as mainly a caching overload event on the IFW-server level and the Development Teams together with the Server Administrators are working hard on a solution.
For the Joomla 3.7-Release the Leadership has decided to place Install from Web in an “offline” state which means that when the user clicks the "Add Install from Web Tab" the plugin and Tab will be shown with a static message "Loading". This is not a bug but intended behavior.
If you still test this with a result seeing the "Loading"....... message you can disable this again by heading to plugins and disable the "install From Web" plugin
The Development Teams believe that this option is an important feature for any administrator and have the intention to resolve the problem as soon as possible and aiming for a resolution in (one of) the next release(s) after J3.7-Stable so the usability experience of the administrator will be again optimized for the installation of extensions.