Recommended workflow for KTX/KTX2 files

I'm using KTX as a source and destination format for HDR and encoded textures, but do image editors like Photoshop have a plugin to export/edit these files? They seem to solely be relegated to a destination format without this kind of support.

There also don't seem to be any pixel editors that can work on mipmaps or HDR, and then save it back to KTX/KTX2. Also Windows thumbnail viewers seem to stop at PNG and DDS. ETC/PVRTC thumbnails on macOS aren't supported due to lack of a decoder. There aren't even any preview utilities for KTX2, and on macOS only ATSC is decoded, and BC is viewable in Preview. PVRTexToolGUI can open mips, but still can't display correct sRGB content, and displays block artifacts on anything larger than ASTC4x4 block sizes.

There just needs to be a little more tooling around KTX and KTX2 to help with all this workflow.

Start by reviewing the workflow gaps listed in the issue and inventory the existing KTX/KTX2 tools, including PVRTexToolGUI and available preview or thumbnail utilities. Narrow the request to one concrete workflow with a named tool and acceptance criteria for editing, mipmap or HDR handling, previewing, or thumbnails.

Written by the indexing model from the issue text.