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   P.S. Bravs doesn’t accept either

You are indeed correct, Alexander. I have tried it in *all* other browsers and it works fine in all but Brave! No fault. Brave just doesn’t accept localhost calls!

(Years later). It might be hard to do. I guess I’m not familiar with how sandboxing would limit things. I have Opera, Firefox, Edge, and Brave apps resident on my iOS/iPadOS devices (in addition to, of course, the Safari app). I have no problem displaying the FTPed copy of my pages in each. But when I select the three dots, upper right, in Textastic, the only browser for which preview is offered is Safari. This is unlike MacOS whereon, in BBEdit, I may elect a preview in any resident browser app.

Having updated to iOS 13.5.1 I do not find that the issue recurs. My htm and css fils are now tidied into one record each, and I have grown accustomed to maintaining them that way (not particularly difficult for e.g., an 889-byte style sheet). I will most assuredly repost if the issue recurs. I can give you a URL of a sample (lorem-ipsum) page if that would be … er … entertaining but I suspect the issue for now is not worth further pursuing. Thanks for your response, Mr. Blach.

[Oops I should've said "theme" writers, not "template" writers. Big difference. My bad