Secure ShellFish might be an option then. It's a file provider for the Files app that connects to SFTP servers. You can open the folder as an external folder in Textastic and changes to files are uploaded automatically. 

Good point. That definitely needs to be improved - also on the iPad Pro without home button.

Hmm, if you save your Markdown files somewhere in the "iCloud" location in Textastic, files are synced automatically across your devices. Am I missing something? 

See https://www.textasticapp.com/v10/manual/managing_files/local_files_icloud.html#icloud for details.

This will be fixed in Textastic 9.0.1.

Thanks for letting me know. I'll look into it. 

While the other settings can be configured per text field/text view, the "." shortcut is a global setting unfortunately. AFAIK there is no way to disable it only in one app since this is handled by the iOS text system.

I will not be able to provide this for all supported languages. What would be the main use case for you? Would supporting HTML, CSS, and JavaScript be a good start ?

This is definitely something that can be improved.

The problem is that all lines in the file need to be laid out again to calculate the new line breaks. For a large file this can take some time and happens in a background thread.

I think I could add code that scrolls the editor once layout is finished.

Due to changes in WebKit on iOS 13, scrolling in the SSH terminal does not work anymore (it worked in iOS 12 and earlier). I already spent a few days trying to make it work again, but I could only get either text selection or scrolling to work, but not both at the same time.

I hope I can fix this in a future update. It may require a rewrite of the whole terminal engine.

Do you know that you can add custom themes to Textastic? See https://www.textasticapp.com/v8/manual/customization/custom_syntax_themes_templates.html

You can find many themes including Tomorrow Night at http://tmtheme-editor.herokuapp.com/#!/editor/theme/Tomorrow-Night (you need a desktop browser for this though).