Problem with Netflix subtitles - text is duplicated and font is small. Problem specific to Firefox - no problem with Chrome or Edge. Problem specific to Netflix - no problem with e.g. Amazon Video. Problem not corrected via Netflix subtitles controls - they have no effect. Problem specific to tab view; subtitles are OK (reasonable size, no duplication) in PiP mode. Problem exists across multiple devices (laptop, desktop) running Windows 10 but no problem using TV.