Gaussian Blur Effect producing different results from 24.1.3 to 24.2 or 24.2.1
The Gaussian Blur Effect "Effect→Blur→Gaussian Blur" is now behaving differently in 24.2 than it was in 21.x. Updating to 24.2.1 did not solve the issue.
The issue: A designer applies a Gaussian Blur to a vector shape and sets the desired blur level to achieve the desired effect. When that file is opened by another user using 24.2 or 24.2.1, copying and pasting the object, or toggling the visibility of the Gaussian Blur effect (in the attributes panel) on the original object will change the visual appearance of the blur (the blur noticeably increases in strength).
This alters the intended design by the designer. If the file is then saved by the 24.2 user and re-opened in 24.1.x or 24.0 (tested), the blur effect will revert to the originally intended visual appearance when the gaussian blur effect visibility is toggled in 24.1 or 24.0. The actual blur value in the gaussian blur settings is unchanged.
For example with an arbitrary number, a gaussian blur effect of value 100 applied to a vector shape in 24.2 produces are larger / stronger blur effect than it does in 24.1 or 24.0.
Also, in 24.2.1, a vector shape with a gaussian blur effect applied to it will appear differently on a white art board background than it will with a white filled vector shape behind it. When a white shape is placed behind the blurred object, the blur appears larger than it does on the white artboard.
Thank you, Adobe / Illustrator team! Today's update (July 29th, 2020 - 24.2.2) has fixed this issue.
If you have a file with a gaussian blur made in 24.0, the visual effect of the blur does not change in 24.2.2 when you toggle the gaussian blur effect visibility.
If you have a file made in 24.0 and had toggled the gaussian blur effect in 24.2.1, causing it to increase in size / change visual appearance, and you now toggle that gaussian blur effect in 24.2.2, it returns to "normal" matching the original file made in 24.0.
Thank you very much! This was critical for our company's work with files supplied by the customer who was using 24.0 while we were on newer versions.
Egor Chistyakov commented
Interesting... Are Document Raster Settings actually the same? I know it’s about different thing, but I have to ask, just in case. Can you provide screenshots?