An emergency update for Wine users has been released today.
As it turns out, yesterday's release no longer reliably detected if OpenMPT was running on Wine, leading to possible wrong configuration defaults being used and a generally degraded experience on Wine-based systems. In addition, playback via Wave Out should now work better on some Wine setups.
If you use OpenMPT on Wine, you are strongly encouraged to upgrade. For other users, there is only one further non-critical bugfix in this release, so you are not required to update.
For a full list new and noteworthy features in OpenMPT 1.26, also read the OpenMPT 1.26.01.00 release notes.