Open a topic that is listed on your profile: https://support.mozilla.org/en-US/user/JaneBurbank/

Beside each of your posts, there is a 3-dot icon. Click it to see 'Edit this post'.

When I click on the three dots, I get "quote" only. There is no edit command.

See the attached picture. As long as you're clicking next to your own post, it should be editable, as I have seen several users, not just contributors, do it.

Look under Question Tools by the OP to edit it.

Can't get to OP editor, and don't know what it is. Clicking on my profile shows no options for editing a communication.

Open the current topic and look for Question Tools in the top right corner under the search box.