Strings containing a colon are partially lowercased when pasted to a text field

Number:rdar://FB8263927 Date Originated:2020-08-04
Status:Open Resolved:
Product:Safari Product Version:13.6
Classification: Reproducible:Yes
When a mixed-case string containing a colon (:) is pasted to an <input> text field in Safari, string part before the colon is lowercased.

Steps to reproduce:
- Open a webpage with an input form, for example
- In the input field, type "TEST:DEMO" (note the colon in the middle)
- Select entered text → Copy → Paste

Observed behavior: pasted string reads "test:DEMO"

Expected behavior: pasted string should be "TEST:DEMO"


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