Can't Map Read-only Volumes

[jaknz]

Describe the bug
Following Docker standards, I should be able to mount a volume as read-only by appending the :ro tag. However it appears CasaOS is silently appending an invisible :rw tag which breaks this functionality.

To Reproduce

1. Create or edit a CasaOS app.
2. Create or edit a Volume mapping
3. Append :ro to target path
4. CasaOS throws up an error indicating that /target/path:ro:rw is not a valid mapping

Expected behavior
The :rw tag is not required to mount a volume, as it is the default behaviour. Expected behaviour would then be for me to be able to specify (or not) this tag.

If you desperately want to include an explicit read-write or read-only tag, would you consider adding a tick box for each volume that indicates write status as read-write (ticked) or read-only (unticked) instead?

Screenshots

Desktop (please complete the following information):
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System Time
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Logs
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Additional context
Running CasaOS v0.4.8, reported as up-to-date.