Textastic already supports the Files app through the "Open…" command. See this topic in the manual for more details:
I mean, when I open ‚on my iPhone‘ in the iOS files App, then there is no topic ,Textastic‘. I need this to downlod files from the browser. I also loaded GoCoEdit, this worked.
Oh, I see. Textastic stores local files in a so-called "application group container" - this was necessary so that Textastic 7 could seamlessly access files stored in Textastic 6. It's also necessary if I ever want to add a share extension that can access local files.
Unfortunately, the Files app currently does not support "On my iPhone" files to be in an application group container. I have reported this as an enhancement request to Apple, but so far this hasn't been implemented by them.
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