ring buffer requested but capture isn't being saved to a permanent file

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I've tried below 2 cases:

1. Ubuntu commandline: sudo wireshark -i wlan0 -k -l -w sniffer_log/1.pcapng -b files:5 -b fiesize: 200000
2. Windows wireshark GUI: Capture->Options->Output->set Permanent file and create a new file automatically and ringbuffer files.

Question: At first, the sniffer started, and log file saved to the permanent files with index and timestamp appended. However, when I stop sniffer, then start, the GUI prompt "Ring buffer requested, but capture isn't being saved to a permanent file". The error prompt disappears only if I click the "Capture->Options->Output" again, no matter choose "start" or "close". Is this a bug? Why it keep prompt the error info even I already set the permanent file and ringbuffer size and file numebrs?