:time reads an ISO date, such as 2026-10-12, or an ISO date and time, such as 2026-10-12T14:03:00Z. Other text, a month that doesn't exist, or a time past 23:59 isn't a date, so the text is shown as written, with no tooltip. Write the date in ISO form.
Incorrect
Opened next friday and merged 2026-02-31.
Opened :time[next friday] and merged :time[2026-02-31].Correct
Opened and merged .
Opened :time[2026-11-02] and merged :time[2026-11-04T09:30:00Z].