Jira Cloud: custom inputs for JQL

We are developing an app that has some custom inputs for JQL. Currently we can only check if the JQL is valid or not on the submit, which is not really user friendly. Additionally, there’s no way to get auto completion. So users have to go issue search first, create jql there, copy it and then paste it to the JQL input box.

So, the question is: have anyone made a custom JQL input that works with Cloud? If yes, please comment here or send me a message, we are ready to pay for such component even with no maintenance.