Opening a link in a new incognito tab from the context menu would lead to crash right now. This is still reproducible if a incognito tab is created by the "+" button.

Another issue: when switching to incognito tab switcher, the "new tab in group" is shown incorrectly.

The crashing bug is tracked here: https://bugs.chromium.org/p/chromium/issues/detail?id=894659

Follow up with comment 2.

If there are more than 2 tabs opened within the same group, some of the sub-tabs and "new tab in group" is shown in the incognito mode as well.

Repro:
1/ Create group by long press and new tab twice
2/ Enter incognito mode (clicking the icon button)


Another issue:
You can scroll(up) the sub-tabs and "new tab in group" that is shown in the incognito mode. Just scroll util those off the screen. Switch back to normal mode, you will notice that the tab group list is scrolled up as well.