I want to know why Session Replay playback shows a blank or unstyled page.
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The Replay player runs on sentry.io and re-fetches your site’s CSS, fonts, and other assets inside an iframe. If those assets don’t allow cross-origin access from Sentry, the replay can appear blank or broken.
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Please try adding CORS headers to those assets, for example:
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Also, please confirm that the assets are publicly reachable and aren’t only available on localhost or a private network.
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If the same replay looks fine on self-hosted Sentry but appears blank on Sentry SaaS, that usually points to a CORS or asset-access issue.
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For more details, see the Session Replay troubleshooting guide.
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If you’re seeing masked text or gray image boxes rather than a completely blank page, that’s likely related to Replay’s privacy defaults. In that case, see Images are not being displayed in my replays.