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In the meantime, I've also acquired the latest ESR 60.X version for other systems, though normally I am a Seamonkey user and am only using Firefox as a back up browser.
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So in this case, it was necessary to select the latest available non-SSE2 required ESR version, which was indeed ESR 45.9, which is what I've got installed now. Only ESRs will comply with that configuration switch value. Yes, the SSE2 compatibility issue was the constraint at hand hence the pre-version-49.0 requirement, but since then I've also discovered that ESRs also allows unverified plug ins / extensions to be installed without being blocked, despite the fact that in the regular Firefox consumer releases, it ignores the ABOUT:CONFIG parameters that disables the plug in signatures requirements. The ESR versions were based on 10.0, 17.0, 24.0, 31.0, 38.0, 45.0, 52.0 and now 60.0 The only reason why you could not use Firefox 49.0 or later versions on Windows is because the CPU you have does not support SSE2. James wrote:There was no ESR based on 48.0.
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