Replace Color No Longer Working Correctly after 26.7

I cannot notice any difference in the result »Replace Color« produces (comparing 26.8.1 and 25.12.3). 

Can you provide steps to illustrate a different behaviour? 

Ideally post screenshots or a screen recording (including all pertinent Panels and dialogs) and the image you work on. 

Replace color is just a rolled-into-one combination of Select > Color Range and Adjust > Hue/Saturation.

It's a non-reversible ("destructive") tool, and as such pretty crude and unforgiving, not really suitable for high-precision and subtle work.

I'd strongly recommend that you work with masked adjustment layers. That lets you use any selection method, which can be tweaked as you go, and any color adjustment tool, with infinitely more control and precision, again tweakable as you go..

For subtle color adjustments, Selective Color is much less disruptive than Hue/Saturation, which tends to tear up the pixel structure in blocks and banding.

Select > Color Range can be used as a selection method, but the standalone function has better controls than in the combo Replace Color.