When you open a PDF from a SharePoint Online Document or List macro link in a Chromium-based browser such as Chrome or Edge, the new tab can fail with an ERR_BLOCKED_BY_CLIENT error. This is a browser behavior, not a permission problem.
Workarounds
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Copy the URL from the blocked tab and paste it into a new tab.
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Right-click the PDF link and select Open link in new tab.
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Install a PDF reader extension in the browser and set it as the default PDF reader, so the link opens in the extension.