Does your log mention database corruption?

No

Include required information

Please be sure to include at least:

• which version of Syncthing and what operating system you are using
  • 1.27.1, but it's even in main
• what happened
  • IDs are of different length from API and in client in specific sections
• what you expected to happen instead
  • same-length IDs

says 7 and therefore from, let's say /rest/system/connections I get first 7 characters as if split on -
and however has the matching one and has even less than both - 5

Shouldn't it be the same everywhere? Would you welcome a patch or is this something you are aware of and it's kept because of some backward compatibility reason?