This appears to be an issue with Oxide reporting the wrong surrounding text offset; it's always out by one when entering new text, so as far as the keyboard's concerned it's still at the beginning of the text field after the first character has been typed. This seems to be due to a synchronisation issue between when Oxide updates the surrounding text data internally and when it reports it to the keyboard.
The reason this doesn't happen with spell check/prediction enabled is that the text is then still in pre-edit and so dealt with internally by the keyboard instead of relying on Oxide's reporting of the surrounding text.
This appears to be an issue with Oxide reporting the wrong surrounding text offset; it's always out by one when entering new text, so as far as the keyboard's concerned it's still at the beginning of the text field after the first character has been typed. This seems to be due to a synchronisation issue between when Oxide updates the surrounding text data internally and when it reports it to the keyboard.
The reason this doesn't happen with spell check/prediction enabled is that the text is then still in pre-edit and so dealt with internally by the keyboard instead of relying on Oxide's reporting of the surrounding text.