I guess I can answer my own question. Seems like it is only intended in std environment https://github.com/siyuan-note/siyuan/blob/928c1d476a4b398bdee3752cc950aed85838bf8f/kernel/util/ocr.go#L347

Can I ask if the maintainers have any reasons why it shouldn't work in docker? Thanks

Thanks for replying. This is exactly what I need. However, do you happen to know why I might not see those buttons?