When I install a FE plugin developed by myself using command install plugin from ...; through mysql-client, the process of installation failed due to my code problems. After I modified the plugin code and reinstalled it using command install plugin from ...;, mysql-client reported an error that the plugin has already been installed. Thus, I used command uninstall plugin ...; to uninstall the plugin for the purpose of next reinstallation, and something unexpected happened that mysql-client reported an another error that the plugin does not exist. In other words，the modified plugin can not be reinstalled.

Display the installed plugins currently using command show plugins; and I find that the plugin mentioned before does not exist.

After logging in the FE node machine, I found that the the directory of plugin mentioned before does exist under $plugin_path. After deleting the directory manually , the plugin mentioned before can be reinstalled successfully.

I think it is a bug. When the installation fails, it is unreasonable to create a directory for the plugin under $plugin_path on the FE.

Next, I plan to fix this bug.