I am seeing consistency across browsers. As for cross-platform, that's a wild card, because folks on the Windows side tend to mess with the settings on their monitors (most commonly, turning brightness way up). Few Mac users use the built-in visual calibration tools and with Windows users it is virtually unheard of. The only way to do it right is for the author to use a properly calibrated system and to use whatever the color sync tools are available (such as what are used with Adobe suites) to achieve consistency across apps. If things look good on our systems, it is the best we can do. We should also be mindful that out-of-the-box Windows machines tend to display colors slightly darker than a Mac.
I will have to experiment with this particular issue. I've been using calibration systems for years, beginning at an art services house in Chicago, working on major national accounts on Barco systems and with a Radius PressView system at home. At present I'm using a Spyder5 with a pair of Apple 27s. I'm going to have to do some experimentation to see what is happening.