The Developer webhooks page embeds a portal panel. If that panel does not appear, one of a few things is usually the reason.
You are not an admin
The Developer webhooks page is for organization admins. A member does not see it in the menu and is redirected away if they open the link directly. Ask an admin to set up the webhooks, or to grant you admin access.
Your plan does not include it
Developer webhooks need the Growth plan or higher. On a lower plan the page shows an upgrade message instead of the portal. Upgrade from Billing to unlock it.
The panel failed to load
The portal is an embedded panel, not a popup, so a popup blocker is never the cause. If the page shows just the title and no panel, the panel failed to load; reload the page to fetch a fresh session. Reload too if you left the page open a long time, since the portal link can go stale.
Frequently asked questions
I see an upgrade message.
Your plan does not include developer webhooks. Upgrade to Growth or higher.
The page is blank below the title.
Reload the page. The embedded panel needs a fresh session.
A member cannot find the page.
It is admin-only and hidden from members.