The color rendering is so different between version 5.x amd 7.x that the user should be able to keep both installed. Reproducible: Always Steps to Reproduce: 1. 2. 3. Works fine here - I just changed the Slot variable for versions 5.x and 7.x in the ebuild from 0 to 5 and from 0 to 7 respectively.
Would also vote for slotting. Otherwise, their is no reason, to stick with numbered subdirs below /opt
There are overlapping files in both releases .. at least the browser plugin. Sorry they cant be installed at the same time.
*** Bug 97371 has been marked as a duplicate of this bug. ***
This really should not be WONTFIX. The colour rendering issues are upstream bugs, some apparent in both Windows and Linux versions, some just the Linux version. Please reconsider this and make the 7 version install the plugins for browsers, and allow 5 to be installed without them for those that need correct colour management and transparency support.