HT-MCS tab hides when setting Band to 2GHz-G/N

RouterOS Wireless Networking
1

there seems to be a bug with the winbox.
I see this bug with version 6.37.1 and version 6.38rc24

When I set the wireless band to 2GHz-G/N (to avoid using 802.11b rates) immediatelly the HT-MCS tab is hidden in winbox.

I attached two screenshots to exhibit this issue.

Here everything is ok:
HT-MCS-gn-nok.png
Here the HT-MCS tab is gone with G/N-rates
HT-MCS-bgn-ok.png

2

Report to support directly.