I recently installed the 20.04 LTS version of Ubuntu. Because all data present in the previous version has been erased and installed, I believe this issue is not a result of the previous data.
It worked normally in Ubuntu 18.04 and 19.10 versions.
- Categories appear, but items contained in categories do not appear. And I can't find the search window.
- Also, when I trying to install software placed on the recommendation list, an error message "Unable to install" occurs. This issue was also found in 18.04 and 19.10 versions.