They can be turned off in Settings | Editor | General | Appearance, Show parameter name hints.
Parameter hints colors are set up in Settings | Editor | Color Scheme | Language Defaults | Inline parameter hint. Try modifying your color scheme to match your preferences
These are parameter hints (see https://www.jetbrains.com/webstorm/whatsnew/, Parameter hints and type info in TypeScript)
They can be turned off in Settings | Editor | General | Appearance, Show parameter name hints.
Parameter hints colors are set up in Settings | Editor | Color Scheme | Language Defaults | Inline parameter hint. Try modifying your color scheme to match your preferences
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