Prusa firmware 6.10.3 for the XL and XL+
A small follow-up to the big 6.10.1 release. It improves chamber temperature estimation and undoes the bed-lowering change. The release before it fixed a display freeze and a resume bug that affected parked tools.
We haven't tested this yet
Prusa released firmware 6.10.3 for the XL and XL+ on 25 September 2026. The full release notes are two lines:
- “Improved chamber temperature estimation.”
- “Reverted bed lowering to the previous behavior.” This undoes the 6.10.1 change that lowered the bed after a print finished, paused or stopped.
The two releases before it
6.10.2 (16 September) fixed a display that could freeze at random, due to an interaction with the Wi-Fi module. It also fixed print resume getting stuck at “Heating”, so parked tools no longer have to cool down before a resume. For the Original XL specifically, it fixed the parking position during tool offset calibration.
6.10.1 (28 August) was the large release: XL+ support, and an early-stage “nozzle thermal expansion compensation” for both machines. Because the XL’s previous firmware was 6.4.2, it also brought across features added to other Prusa printers since then. Those include tool mapping that’s kept when you reprint, Load/Unload All, an immediate stop on filament runout, and a fix for layer shifts during fast curved moves.
What we’ll run
We’ll record the exact firmware on our XL before each test run. If an update lands mid-series, runs before and after it are kept separate rather than averaged together.