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Pages for Bitbucket has Global and Repository configuration levels.

Global configuration

Click the Administration icon ⚙️ > Pages configuration to open the Pages configuration page.

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Select a repository, then click Repository settings > Web Pages to open the Repository settings page.

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Security levels

Select one of the following web page content protection levels from the Allow insecure Javascript / HTML / CSS content field:

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Enter the path used as root of web server in the Sub-folder to serve field. Using this option limits access to the repository through the web server. Only the contents of the specified folder are served as pages.

Enable branches

If the Automatically enable pages for new branches in this repository option is enabled, the web page link is enabled for all newly created branches. You can also manually enable or disable particular branches or tags.

Web Page navigation link

If a branch link is enabled, you can select it to be used with the Web Page button in the navigation bar:

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