Configurations

1. Open your TYPO3 setup.

2. Follow the steps below, before the extension upload to prevent any error in extension installation in the latest versions of TYPO3 (specifically 12.x.x & 13.x.x here).
    Ref.: https://forge.typo3.org/issues/100730

3. Go to Admin Tools > Settings > Extension Configuration and click on Configure extensions

4. Then the popup will open as seen below screenshot, in that popup go to the extensionmanager > Install extensions automatically after download from TER or file upload (basic.automatic Installation [boolean])) and uncheck the checkbox & click on the Save “extensionmanager” configuration button.