Semantic-Ui modal jittery behaviour-open source projects Semantic-Org/Semantic-UI

I am using Semantic-UI for designing a site for my project and I while using modal, I am seeing a jittery behaviour.

Here is the link : Click Here to Enter The Project Site

Press the ‘Register’ button to open up the modal dialog, and you will notice the dialog being formed in the left side and then shows up properly.

Cannot understand the reason for this behaviour.

Some help will be appreciated.

Code :

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