diff --git a/.changelog/5985-fix-css-module-hash-project-root.md b/.changelog/5985-fix-css-module-hash-project-root.md
new file mode 100644
index 0000000000..606316bc0c
--- /dev/null
+++ b/.changelog/5985-fix-css-module-hash-project-root.md
@@ -0,0 +1,3 @@
+### Changed
+
+- Hashed CSS class names no longer depend on the build machine's checkout path, in PR [#5985](https://github.com/microsoft/BotFramework-WebChat/pull/5985), by [@OEvgeny](https://github.com/OEvgeny)
diff --git a/esbuildPlugins.mjs b/esbuildPlugins.mjs
index 8a624828ba..5bd2aac4d1 100644
--- a/esbuildPlugins.mjs
+++ b/esbuildPlugins.mjs
@@ -1,3 +1,4 @@
+import { fileURLToPath } from 'url';
 import lightningCssPlugin from 'unplugin-lightningcss/esbuild';
 
 // Due to a bug in unplugin, we cannot use the Lightning CSS unplugin directly.
@@ -18,7 +19,10 @@ const cssPlugin = {
           animation: false,
           grid: false,
           customIdents: false
-        }
+        },
+        // Hashed class names come from the file path relative to this folder (the repository root):
+        // the same on every machine, and different for modules at the same path in different packages.
+        projectRoot: fileURLToPath(new URL('.', import.meta.url))
       }
     }).setup({
       ...build,