According to Adobe’s original release notes for this patch (February 2018), this build resolved the following:
While Photoshop CC 2018 was not a revolutionary leap from CC 2017, version 19.1.1 focused heavily on refinement. Here are the standout features as they existed in this specific build: Adobe Photoshop CC 2018 V19.1.1.42094 -x86-x64
A: The 32-bit architecture is limited to ~3.2GB of RAM. Any image exceeding ~200 megapixels or with 50+ layers will likely crash. Use the x64 version. According to Adobe’s original release notes for this
At 90%, the screen flickered. It wasn't a glitch this time. For a split second, the installer window lost its modern UI edge and looked like something from Windows 95—a brief flash of grey, stark text, and a progress bar made of sharp blocky squares. Adobe Photoshop CC 2018 V19.1.1.42094 -x86-x64