I think it's a recent phenomenon and not related to rendering of ads.
I use Chrome and it's quite common, but not always. I would turn up the developer console and find thousands of errors and warnings when I notice the tab icon keeps blinking. The errors are mostly blocking of third-party plugins, security domain violations or similar content policy enforcement. And it just keeps reloading the same requests.
I don't have any ad blocking or any extension installed so this should be a wide spread thing. It's probably overzealous ad providers ignoring Chrome's security policies.
I use Chrome and it's quite common, but not always. I would turn up the developer console and find thousands of errors and warnings when I notice the tab icon keeps blinking. The errors are mostly blocking of third-party plugins, security domain violations or similar content policy enforcement. And it just keeps reloading the same requests.
I don't have any ad blocking or any extension installed so this should be a wide spread thing. It's probably overzealous ad providers ignoring Chrome's security policies.