4.17.3 - Fix issue with proxies in UC Mode

Fix issue with proxies in UC Mode

• Fix issue with proxies in UC Mode
  --> This resolves #1995
• Also Refresh the pdbp (Pdb+) dependency

What's Changed

• Fix issue with proxies in UC Mode by @mdmintz in #1997

Full Changelog: v4.17.2...v4.17.3