I am still bothered by this and Google has not released another version yet. Any ideas, please?
Today I upgraded from Google Earth Pro 7.1.7.2602 to the recently released 7.1.8.3036 and I immediately noticed a problem. The font used by default in all placemark balloons changed from sans-serif to a small serif one. This affects not only all of my own placemarks but those from the standard Layers. For my eyes the old font was already marginal and the new one is simply unworkable. I know I can change the <BalloonStyle> for my own placemarks but for several reasons I don't want to do that, and it still would not fix the font in the standard Layers.
How can I control this font? It does not originate in myplaces.kml as that file is unchanged.
7.1.7.2602 balloon font:
7.1.8.3036 balloon font:
Best Answer
After upgrading to Google Earth Pro 7.3.1.4505 64-bit, released January 22nd, 2018, I was pleased to see that a more readable font has been restored:
(The missing images in the pop-up are because Trimble Outdoors is no longer supported.)