Improve Pipedream Connect docs to add solution for the Pipedream Connect popup not opening

docs-v2/pages/connect/managed-auth/quickstart.mdx

@@ -97,6 +97,10 @@ npm i --save @pipedream/sdk
 
 When the user connects an account in your product, [pass the token from your backend](#generate-a-short-lived-token) and call `connectAccount`. This opens a Pipedream iFrame that guides the user through the account connection.
 
+<Callout type="info">
+If the Connect popup window doesn't open and your site sets the Cross-Origin-Opener-Policy (COOP) header to `same-origin`, set it to `same-origin-allow-popups` on the page that embeds the Connect iframe. The default COOP is `unsafe-none`; only make this change if you explicitly enforce `same-origin`. This relaxes isolation just enough to allow trusted popups (e.g., OAuth) to open from iframes.
+</Callout>
+
 Try the interactive demo below to connect an account after generating a token in the previous step:
 
 <div className="not-prose">

docs-v2/pages/connect/managed-auth/troubleshooting.mdx

@@ -46,6 +46,11 @@ Double-check the app slug you're passing [when connecting your user's account](/
 
 The user may have closed the OAuth popup window without completing authorization.
 
+### Connect popup doesn't open
+
+If the Connect popup window doesn't open when users try to connect their accounts, the host page may be enforcing the Cross-Origin-Opener-Policy (COOP) header with the value `same-origin`, which isolates the browsing context and can interfere with popups opened by cross-origin iframes.
+
+Set the `Cross-Origin-Opener-Policy` header to `same-origin-allow-popups` on the page that embeds the Connect iframe. The default COOP is `unsafe-none`; only apply this change if you currently send `same-origin`.
 <Callout type="info">
 If you're still have trouble or hitting an error that isn't listed here, [get in touch with us](https://pipedream.com/support). We'd love to help.
 </Callout>