hey - we are closer now (or am I colour blind?).
The sole image that is different here is the left preview in the "safe for web" tool.
At the beginning of the thread I asked you to use the "safe as" command.
What happens if you convert your AdobeRGB image to sRGB and then "safe as" JPG and open it in Mac Preview (or Safari or both)?
Step 2, but I should point out that it looked nothing like this on screen. The images were far far less saturated, rather grey looking, in fact.
brilliant. Don't worry about saturation. For the screenshot your display profile is assigned and that's why it looks different here.
Essential is only: what matches and what matches not. And it's only the "safe for web" tool that is off (only on the left side) while the rest is on a par.
So: there is a bug with the "safe for web" tool, okay.
BUT: you can work with my third Monitor Profile as this seems to work - at least in a way that you can work in Photoshop and convert to sRGB and get the same in the web (actually you could use the "safe for web" tool as well but you should ignore the left image and compare the regular Photoshop window with the output of the Safe for web" tool on the right side).