Even if you go to F12 under Security, you still can't see the certificate. Works fine in Chrome.
@scottbroadway: View certificate in the developer tools will be fixed later (separate issue: #2611).
Suspicious that this remains an issue... did I miss a thread elsewhere?
This will be fixed in brave-core. Here's a screenshot of it.

Closing the issue as fixed-with-brave-core
Verified as fixed in brave-core with https://github.com/brave/browser-laptop/issues/15064#issuecomment-415181577
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This will be fixed in brave-core. Here's a screenshot of it.

Closing the issue as
fixed-with-brave-core