I may have inadvertently changed some Firefox security setting, but don't know which one. Or, as likely, due to a recent Firefox update. I try to keep up-to-date. Here is the link and error log from Firefox (if I copy just the link to Safari, it works fine): The resource at “https://dmt.fidelity.com/privacy/v1/b/b.rnc?n=15&c=65&i=55ti80&p=prod&s=2348&d=8ER7InZlcnNpb24iOiIxLjAuMCIsImdhdGV3YXkiOiIyLjMuNjgyIiwiY2xpZW50SWQiOjY1LCJwdWJsaXNoUGF0aCI6InByb2QiLCJpbnN0YW5jZSUAYCI1NXRpOE0A8ApwYWNrZXQiOjcsIm1vZGUiOiJlbmZvcmNlVQDwDG9va2llcyI6eyJTdHJpY3RseSBOZWNlc3Nhcn8AsDEiLCJQZXJmb3JtWQAAowDTIiwiRnVuY3Rpb25hbBEA8kZUYXJnZXRpbmcgYW5kIEFkdmVydGlzaW5nIjoiMCJ9LCJlbnZpcm9ubWVudCI6IkFsbG93ZWQgRG9tYWluIiwicmVxdWVzdHMiOlt7ImRlc3RpbmF0EwHwAmh0dHBzOi8vcGR4MS5xdWFspwCUcy5jb20vV1JREADwJlNpdGVJbnRlcmNlcHQvR3JhcGhpYy5waHA_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_gw8RBlsB8gMiZW6uBQMlBjc3NDSAAg8RBkIP-AMKDwIBXC4zOYIDCQIBDxEGQ8A0NzE4OTQ2NjB9XX0” was blocked by OpaqueResponseBlocking. Reason: “after sniff: nosniff is true”.