Firefox 56.0.1
https://www.mozilla.org/en-US/firefox/56.0.1/releasenotes/
Fixed
Block D3D11 when using Intel drivers on Windows 7 systems with partial AVX support (bug 1403353)
Changed
Users of 32-bit Firefox on 64-bit Windows are migrated to 64-bit Firefox for increased stability and security.
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Note: My 32-bit version [in the Program Files (x86) directory] was over-written with the x64 bit version. Fortunately, all my add-ons (extensions) are still working... for now.
- Internal updater via Help / About Firefox