Setting pedal and (de)crescendo lines to invisible doesn't work in PDF export and uploading
Look for measure 237 in https://musescore.com/howard_c_/scores/5398878 for crescendo lines, and look for anywhere beneath the piano staves for pedal lines. These lines have their element properties set to invisible, but the line parts don't make themselves invisible. Which causes the PDF convertion and online-uploaded pages to have those lines visible on them.
For further reference see the discussion below #279510: Invisible pedal marks visible on musescore.com.