Should I update?

Should I update Lightroom Classic?

Lightroom Classic 15.4 · Fixed bug

Develop histogram RGB readouts freeze while editing sliders

Fixed in Lightroom Classic 15.5, according to Adobe’s release notes. The bug was reported for Lightroom Classic 15.4. It happens on macOS only.

Status
Fixed in 15.5
Severity
Major
Affects
Common workflow
System
macOS only

The fix · Lightroom Classic 15.5

“RGB and LAB color readouts don't work in the Histogram.”
Adobe’s release notes

Workaround · if you stay on Lightroom Classic 15.4

Click outside the numeric field or press Escape to restore live histogram RGB/LAB readouts.

Timeline

  1. Jun 30, 2026Reported on Lightroom Classic 15.4
  2. Aug 4, 2026Fixed in Lightroom Classic 15.5per Adobe’s release notes

The report

8 votes · 12 replies

Reported on Windows by 1 person, on macOS by 2 (from the report and 12 replies).

“P: LrC 15.4 Persistent RGB/LAB readouts in Histogram not working in Develop”

Read it on the Adobe Community board
Should you update Lightroom Classic today?Today’s verdict for Windows and macOS, and every known issue behind it.

Based on public bug reports on the Adobe Community board. Last changed October 6, 2026. The title and rating are ours; the report is the reporter’s. Not affiliated with Adobe.