I installed a new instance and it work fine but when I try to change the theme it broke down and come with the broken theme. but somehow I fixed it. But when I try to change the module name it is not working showing a blank screen. There are no sugar logs as well.
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The file permissions are right as well.
sudo chmod -R 755 .
sudo chmod -R 775 cache custom modules themes data upload config_override.php
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My version 7.12.3
I have recorded the process: https://nimb.ws/w3yUX9
Any advice would be appreciated. Regards