not honoring :pdf-theme: attribute

[mvolkmann]

I have this in my document header:

:pdf-theme: custom-theme.yml

The file custom-theme.yml is in the same directory as my book.adoc file.
When book.adoc is open and focused in VS Code and I select "AsciiDoc: Export Document as PDF" from the command palette, it generates the PDF, but does not use the custom theme.
But when I enter asciidoctor-pdf book.adoc from a terminal, it does use the custom theme.
Is this is known issue?

Here are my VS Code details:

Version: 1.106.2 (Universal)
Commit: 1e3c50d64110be466c0b4a45222e81d2c9352888
Date: 2025-11-19T16:56:50.023Z
Electron: 37.7.0
ElectronBuildId: 12781156
Chromium: 138.0.7204.251
Node.js: 22.20.0
V8: 13.8.258.32-electron.0
OS: Darwin arm64 24.6.0

The AsciiDoc VS Code extension I have installed is version 3.4.5.