I can see similar problems when editing text files in OneDrive using the Runestone app:

• In Runestone, I opened a file from OneDrive
• I added a line
• Hit "Done" to close the file
• When I open the file again, my changes are not visible

In iA Writer, I also see changes disappearing, but the behavior is different than in Textastic and Runestone.

So it looks like Microsoft has a bug in their OneDrive file provider.

I just tried to reproduce the issue with OneDrive on my iPhone:

• Use "Open…" to open a text file from OneDrive
• Add text to the file
• Close the file

When I now open the file again from "Recent Files" in Textastic, the changes I made to the file are not there. 

But, if I open the file again using the "Open…" command, the changes are there! Also, when I view the file in the OneDrive app, I can see the changes.

Can you please try to view the file in the OneDrive app or use "Open…" to open the file again?

This looks like a bug in the OneDrive file provider.

Also, there is a file version history on https://onedrive.live.com/ under "My Files" where you can restore previous versions of the file. See https://support.microsoft.com/en-us/office/restore-a-previous-version-of-a-file-stored-in-onedrive-159cad6d-d76e-4981-88ef-de6e96c93893

I'm hopeful that you can use that to restore your file in case using "Open…" again does not work.

TOML support has been added in Textastic 10.9.2 which was just released.

Textastic for Mac does support find in files. 

See Edit > Find in Files… or Cmd-Shift-F.

I'll consider adding TOML as a built-in language in a future update.

You can add custom syntax definitions to Textastic by using TextMate bundles or Sublime Text packages. See

https://www.textasticapp.com/v10/manual/customization/custom_syntax_themes_templates.html

A quick search for "TOML sublime text" on Google brought up this Sublime Text package which I just tried out and which seems to work fine with Textastic:

https://github.com/jasonwilliams/sublime_toml_highlighting

Please try the following:

• Go to https://github.com/jasonwilliams/sublime_toml_highlighting in Safari on your iPad/iPhone
• Tap the green "Code" button and select "Download ZIP"
• Unzip the file in the Files app. This will create a folder that contains the sublime package files. (Optionally you can rename this folder to "TOML")
• Move or copy that folder into the folder "On my iPad/Textastic/#Textastic/". This is equivalent to this folder in Textastic: "Local Files/#Textastic/".
• In Textastic, go to Settings -> Other and tap "Reload Customizations"

You can now select "TOML" from the list of syntax definitions in the File Properties.

Please note that this is a third-party syntax definition, not officially maintained by Textastic.

Here is a screenshot of how this looks in Textastic with a sample TOML document and the Vintage theme:

The SCP Wikipedia article links to the following 2019 quote of the OpenSSH team: "The scp protocol is outdated, inflexible and not readily fixed. We recommend the use of more modern protocols like sftp and rsync for file transfer instead."

Textastic already supports SFTP and I don't have plans to support SCP, sorry.

In case you don't want the app, you can request a refund from Apple on the following website: https://reportaproblem.apple.com

The macOS version and the iOS/iPadOS version of Textastic are two separate apps for two different platforms with different feature sets (the macOS version doesn't have remote connection support), so it would require two purchases if you want both.

The macOS version is available as a one-time purchase on the Mac App Store. A trial version is available on the website.

Textastic for iOS is a free download with in-app purchases. It offers a 7-day free trial when starting a monthly or yearly subscription, so you can explore all features before deciding to buy. If you prefer not to subscribe, a one-time purchase option is also available.

Offering a free download with in-app purchases is currently the most practical way to provide a trial through the iOS App Store.