Hi Ted,
Ye can change from default for ICCV4 in Firefox through
"about:config". (Worth a read if yer unfamiliar with it)
Clear the address bar. Type in about
:config ( no quotation marks), click "enter". Click through the "here be dragons - I'll be careful" page.
Scroll down tae " gfx.color_management.enablev4"
On the right hand side of the page are 3 columns....STATUS -TYPE-VALUE (at the top of the page)
In the columns, if ye haven't changed the setting before it will read DEFAULT - BOOLEAN - FALSE
Right click on "false" and toggle it tae "true". Close Firefox and then re-open.