I used to work with Sharepoint 2013 OnProm with Content Editor webparts from where I can just embed an HTML file and some JS scripts.
I'm now looking at Sharepoint Online in my organization. I'm a Site Collection Admin, but I don't have tenant permissions (which is reserved for a very small number of people inside my company's IT team).
I looked at the way to create webparts with SPFx, but it seems the deployment always ends with publishing the webpart to the Tenant App Store... Which I don't have access to.
There is no Content Editor webpart in my Site Collection (maybe it hasn't been activated by my IT?!), and if I upload an .html file in a doc library, I cannot open it directly (it will force a download of the file).
I'd like to create a Single Page Application, or at least a webpart. But without Tenant permissions, what are my options here? Knowing that I cannot ask to my IT team to change anything at this stage (I cannot request Site Collection App store, or to enable Content Editor).