Reload preview with VSCODE_PROXY_URI ignores the value

[micedre]

I have:

• searched the issue tracker for similar issues
• installed the latest version of Quarto CLI
• formatted my issue following the Bug Reports guide

Bug description

When using quarto preview with the VSCODE_PROXY_URI the url displayed is the good one (as was done in to #1542), but editing the previewed file, cause a reload to the root url ignoring the value in VSCODE_PROXY_URI

Steps to reproduce

In a code server environment (or with an env variable VSCODE_PROXY_URI) quarto createan empty website. Enter the new directory and executequarto preview`.

The preview url is the good one (evaluated against VSCODE_PROXY_URI).

Then edit the index.qmd file, the broser should reload at the root of the url (without the path indicated in VSCODE_PROXY_URI)

Actual behavior

No response

Expected behavior

No response

Your environment

No response

Quarto check output

Quarto 1.9.37
[✓] Checking environment information...
      Quarto cache location: /home/onyxia/.cache/quarto
[✓] Checking versions of quarto binary dependencies...
      Pandoc version 3.8.3: OK
      Dart Sass version 1.87.0: OK
      Deno version 2.4.5: OK
      Typst version 0.14.2: OK
[✓] Checking versions of quarto dependencies......OK
[✓] Checking Quarto installation......OK
      Version: 1.9.37
      Path: /usr/local/lib/quarto-1.9.37/bin

[✓] Checking tools....................OK
      TinyTeX: v2026.04
      Chromium: (not installed)
      Chrome Headless Shell: (not installed)
      VeraPDF: (not installed)

[✓] Checking LaTeX....................OK
      Using: TinyTex
      Path: /home/onyxia/.TinyTeX/bin/x86_64-linux
      Version: 2026

[✓] Checking Chrome Headless....................OK
      Chrome:  (not detected)

[✓] Checking basic markdown render....OK

[✓] Checking R installation...........(None)

      Unable to locate an installed version of R.
      Install R from https://cloud.r-project.org/

[✓] Checking Python 3 installation....OK
      Version: 3.13.12
      Path: /opt/python/bin/python3
      Jupyter: 5.9.1
      Kernels: python3

[✓] Checking Jupyter engine render....OK

[✓] Checking Julia installation...

[micedre]

From what I understand, the root cause seems to be in src/webui/quarto-preview/src/server/navigation.ts the match does not include paths like /proxy/{{port}}

[cscheid]

@cderv Just a reminder that PRs in this area need a review from Positron because there's interactions with how they interpret vs code information.