From a 2022 report, trivially searched-for on Google:
> According to the Federal Aviation Administration, more than three dozen instances of cracked windshields have been reported by airlines over the past five years.
Takeoff/landing cycles, actually. Cruising at high altitude is much less rough on the airframe (including windows) than the strains that happen when changing altitude.
The most infamous incident with a cockpit window is probably British Airways Flight 5390. An incorrectly installed window blew out, causing one of the pilots to be partially ejected.
This article from 2014, predating all of Boeing's recent failures, claims it is a regular occurrence and is also not always reported because it's a relatively minor thing to happen:
