As of October 19th， a significant bug affecting a large number of users has emerged following the release of version 0.95 of Microsoft’s popular open-source toolset， PowerToys. This issue causes Windows 11’s theming mode to automatically and frequently switch between dark and light modes.
Microsoft has since confirmed that this erratic behavior stems from an option that was not intended to be enabled by default. Due to PowerToys running silently in the background， many users were unaware that this tool was the cause of the disruption.
Numerous users have expressed their frustration on communities like GitHub. One affected user shared， “I spent an hour trying to figure out what was tự động switching my Windows theme from dark to light.”
Another user described the theme being forcibly changed every 30 seconds， leading them to suspect either a Windows component malfunction or even malicious software， resulting in valuable debugging time being wasted.
The root of this bug lies within a new feature in PowerToys v0.95 called “Light Switch.” This feature was designed to implement a long-anticipated automatic theme switching functionality， allowing users to toggle between dark and light modes based on time or sunrise/sunset. This type of automated transition is a common user-requested feature in modern operating systems， aiming to enhance user comfort and reduce eye strain， especially during different times of the day.
Typically， new features added to PowerToys are disabled by default to avoid disrupting user workflows. However， Microsoft developers have confirmed that the “Light Switch” module was inadvertently enabled by default， triggering the disruptive automatic theme switching. This oversight represents a notable deviation from Microsoft’s usual meticulous testing and rollout procedures for their popular utility suite.
For users who were unaware of the cause， even manually changing the theme back to their preferred mode in Windows “Settings” would see PowerToys forcibly revert it to the opposite theme in a very short period. This aggressive override made the issue particularly persistent and difficult to resolve without direct intervention within PowerToys itself.
Affected users can resolve this issue by opening PowerToys， navigating to the system tools settings page， and ensuring that the “Light Switch” feature is turned off. This action will prevent Windows themes from continuing to switch automatically.
