This is a patch release containing the following changes: 2461: Prevent memory from exploding when particles get too spread out 2469: runForClockTime() updates currentStep correctly 2508: Fixed handling of insertion codes in PDBx/mmCIF files 2511: Add support to ForceField for handling SMIRNOFF trefoil impropers 2542: Catch exception when an OpenCL platform has no devices 2544: Fixed error on CPU platform when forces disagree about whether the system is periodic 2553: Fixed incorrect indexing in kernel 2557: Replace nonstandard atom and residue names when loading PSF files 2563: Add chain break when either auth_asym_id or label_asym_id changes 2569: fix performance issue when use Drude force with velocity-verlet integrator 2572: PDBxFile marks heterogens with HETATM 2575: Improved identification of chain IDs in PDBx/mmCIF files 2587: Switched dlopen flag from RTLD_GLOBAL to RTLD_LOCAL 2592: Fix error loading CPU PME on Mac 2631: Fixed errors in sorting on some AMD GPUs 2644: Fixed an edge condition that could cause errors in CMAPTorsionForce 2657: bugfix for simulation.runForClockTime()