Lightroom Classic PDF book color profile doesn't apply ?

Hi, I'm trying to generate a PDF book for on screen  viewing using the Book module in LR Classic (latest update as of today). The source images are all fully rendered jpegs in the sRGB colorspace. When the resulting pdf is viewed on a wide gamut monitor the images are rendered oversaturated, although I specified sRGB as profile in the book settings. They look OK on a standard sRGB monitor, so I think that the color profile isn't embedded in the LR-generated PDF. Am I doing something wrong or is this normal behaviour? I expected a pdf book to render colormanaged using the embedded color profile...

Thanks for your help,

Dirk