When pdfBug is true, the substitution font is used in the text layer in order to be able to know what is the font really used thanks to the devtools. And to be sure that fonts are loaded, the font cache isn't cleaned up when the debugger is active.
structuredClone
unicorn/prefer-optional-catch-binding
createPromiseCapability
PromiseCapability
Metadata
class
unicorn/prefer-ternary
GlobalWorkerOptions