Verified update history
Firevolt’s June demo update targeted connection stability and a DLSS problem that could affect the first few launches. It also published earlier handling and performance adjustments before withdrawing the demo to focus on release.
On launch day, Firevolt also shipped a login hotfix in Build 25066538 for players who could not sign in. Restart Steam, verify that both partners are on Build 25066538 or later, and retry before treating a login failure as a network-routing problem.
Those historical fixes are useful context, but they are not proof that hotfix build 25066538 is free of desynchronization, latency, stutter, or device-specific issues. Community hub reports can identify symptoms, yet a report from one network or demo build is not a universal diagnosis.
Conservative troubleshooting
Confirm that both players use the current build, restart the lobby after a version mismatch, and test a wired or stable low-latency connection where possible. On PC, update graphics drivers and compare DLSS off versus the appropriate quality preset if the symptom is visual or first-launch related.
Do not change several variables at once. First separate network position divergence from low frame rate; then separate a general GPU issue from an upscaler-specific one.
Reporting useful evidence
Record the build, GPU, driver, host/client role, co-op mode, and exact room where the fault occurs. Recheck current Steam announcements before applying a demo-era workaround. This page remains mixed because launch reports and patches were still changing on September 2, 2026.