Sample challenge page: Keyboard focus does not move to the popup and is not trapped in the challenge prerequisites popup.

Steps to Reproduce

1. Go to the sample challenge page: https://www.topcoder.com/challenges/30095347.
2. Activate the 'register' button'.
3. There is a poppup which appears with details about the challenge prerequisites.
4. Note that keyboard focus doesn't move to the poppup and is not trapped inside this poppup, instead we are able to access the elements in the main page.

Expected Result Keyboard focus should move to the poppup and should not be able to access the elements in the main page till the poppup is dismissed.

Actual Result Keyboard focus doesn't move to the poppup and is not trapped inside the poppup.

Device: Desktop/Labtop Operating System: Windows Browser: Chrome

WCAG Category: 2. Operable WCAG Level: A WCAG Success Criterion: 2.1.1 Keyboard Screen Reader Used: JAWS Accessibility Audit Tool used: N/A

Attachment https://topcodermsft-my.sharepoint.com/personal/pd-topcoder_topcodermsft_onmicrosoft_com/Documents/Forms/All.aspx?cid=088f5f5d%2D9b1c%2D4b7e%2Dacbf%2D320c257c9a9a&FolderCTID=0x0120005C598A51049FC14CBA882E1AEE168F51&id=%2Fpersonal%2Fpd%2Dtopcoder%5Ftopcodermsft%5Fonmicrosoft%5Fcom%2FDocuments%2FMSFT%2DTeams%2DQA%2FJune%202019%2F29%20Jun%2FTest%20Results%2FBug%20Videos%20%26%20Log%20Files%2FKameshwarid%2Fbug%2033

Final Submission Guidelines

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