I don't quite know how to explain the problem, so please pardon me if this seems hard to understand. I have a twilight exterior photo that I processed so that the blues have a slight purplish bias, using Photoshop and Lightroom. When I export (as a jpeg with an sRGB profile) and view that photo in various other applications such as Firefox, Canon Image browser and Apple Preview, the photo looks as I intended it. However, when I look at the photo online in iWeb, those blues with the purplish bias now have a cyan bias. When I download the image from the iWeb website, I can see that it has retained the sRGB profile with which I exported it originally. However, when I view that downloaded photo with Firefox, Preview, Photoshop, etc., it still has the cyan bias that I see in the iWeb website. My understanding is that iWeb is html and a color managed application. What I seem to be seeing looks like lack of color management. I have come to expect (and detest) this lack with Adobe Flash, but I did not expect it from an html application. Still, I am puzzled why the downloaded photo looks non-color managed when it has apparently retained its sRGB profile and is viewed in color managed applications.
By the way, I did not create the iWeb website. Is there perhaps some setting related to color management in iWeb? Also, other twilight photos on this website look as I intended. The photo in question was added to the website at a later date by the same person who created the website.