I saw many issues here about "Integrations" and apparently everyone knows what they are about :)
But... I'm completely lost here.
What exactly are Integrations, those that we set up in "integrations_*_url" ?
What is the purpose of them?
What do I lose if I disable Integrations?
Integration are bots, bridges and widgets that you can add to a room in matrix. They are managed by a separate piece of software, the 'integrations manager'. Today I know of two integrations managers - Scalar (the New Vector proprietary implementation that provides integrations for matrix.org) and Dimension an open source implementation.
Bots are fairly self-explanatory, widgets are small web applications you can embed into the matrix client experience (such as a jitsi video conference, or a google doc, or etherpad). Bridges connect matrix to external platforms such as IRC or Slack or Gitter.
The integrations_*_url config is (I think) associated with connecting your client to an integrations manager.
If you're using https://riot.im/app connecting to matrix.org you'll be able to try out all of the integrations - click the four squares icon in the top right:

and you'll get a modal window to add and configure integrations:

@lampholder Perfect explanation! Thank you very much.
What is the specific setting to get rid of BOT SETTINGS "You need to be able to invite users to do that."? Can't invite any giphy,google,guggy etc bots.
What is the specific setting to get rid of BOT SETTINGS "You need to be able to invite users to do that."? Can't invite any giphy,google,guggy etc bots.
I am in the same boat.