In current scenario, we will be disabling the 'theme enable' for the everyone. Similarly, we can use the same technique to enable the 'theme enable' dialog.
User should have admin permission to enable/disable this setting.
Open 'Vamhi Kali : User Settings' by going to
Administration > Manage Apps
Click on 'Vamhi Kali : Settings' form the sub menu
To enable/disable the dark theme property by checking/unchecking the checking box.
Click on Save button.
After you see confirmation message, hard reload your browser by cleaning your local cache.
(Tip : Ctrl/Cmd + Shift + R to hard reload chrome browser)
You're all set! This disables the 'theme enable' dialog for everyone using Jira.