Hello Kris,
Thank you for posting your question on the Microsoft Windows Forum!
The most important finding is that the issue appears only when the applications are displayed on the external monitor, while the menus and text render correctly on the laptop's built-in display.
This suggests the problem is more likely related to:
Display scaling
DPI awareness
Graphics driver rendering
Multi-monitor display handling
rather than corruption of the applications themselves.
What this means
Because the issue is affecting multiple Windows applications:
Paint
Snipping Tool
Photo Viewer / Photos
at the same time, a recent application update is less likely than a common factor such as:
A Windows update
A graphics driver update
A change in display scaling
An issue specific to the external monitor
Highest-value next step
I would first check whether the external monitor is configured with a different scaling setting than the laptop display.
Navigate to:
Settings
→ System
→ Display
and compare:
Scale
Resolution
Refresh Rate
between the laptop screen and the external monitor.
As a quick test, temporarily set both displays to:
100% scaling
and verify whether the menu text continues to appear scrambled.
Additional check
If the issue started approximately one week ago, it may also be helpful to review whether a recent graphics driver or Windows update was installed around the same time.
Check:
Settings
→ Windows Update
→ Update History
and:
Device Manager
→ Display Adapters
→ Driver
to see whether the behavior coincides with a recent update.
Microsoft Reference
Fix screen scaling issues in Windows: https://learn.microsoft.com/en-us/answers/questions/5764308/how-do-change-the-size-of-the-display-to-fit-the-m
One clarification
Could you let us know:
The laptop model
The graphics adapter (Intel, NVIDIA, AMD)
The external monitor model
Whether the issue occurs on all external monitors or only one
Those details will help determine whether this is related to Windows display scaling, a graphics driver issue, or a recent update affecting multi-monitor rendering.
I hope this answer has brought you useful information. If so, please click on "Accept Answer" and consider upvoting it. Doing so helps other community members identify useful solutions to similar issues.