diff --git a/static/build.html b/static/build.html
index 5fb58a8a..ff62d0ec 100644
--- a/static/build.html
+++ b/static/build.html
@@ -250,6 +250,7 @@
                     <p>Additional dependencies for extracting vendor files with adevtool:</p>
 
                     <ul>
+                        <li>Optional: venv module for Python 3</li>
                         <li>protobuf library for Python 3</li>
                         <li>Node.js 18 LTS</li>
                         <li>yarn</li>
@@ -382,11 +383,44 @@ source build/envsetup.sh
 lunch sdk_phone64_x86_64-ap2a-user
 m aapt2</pre>
 
+                    <div class="notice">
+                        <p class="notice-heading">Optional</p>
+
+                        <p>Run the following additional commands once to create a working
+                        environment if your Linux distribution (such as Debian bookworm) doesn't
+                        have the Protobuf library for Python 3 package version (5.)27.2 or later.
+                        This installs the latest library version in a Python 3 virtual
+                        environment.</p>
+
+                        <pre>python3 -m venv venv
+source venv/bin/activate
+pip install protobuf
+deactivate</pre>
+                    </div>
+
+                    <div class="notice">
+                        <p class="notice-heading">Optional</p>
+
+                        <p>If you have installed the Protobuf library in the Python 3 virtual
+                        environment, activate the environment:</p>
+
+                        <pre>source venv/bin/activate</pre>
+                    </div>
+
                     <p>Download, extract and prepare the vendor files:</p>
 
                     <pre>adevtool generate-all -d <var>PIXEL_CODENAME</var></pre>
 
                     <p>Replace <code><var>PIXEL_CODENAME</var></code> with Pixel device codename, which is the same as <a href="#build-targets">build target name</a>.</p>
+
+                    <div class="notice">
+                        <p class="notice-heading">Optional</p>
+
+                        <p>If you have installed the Protobuf library in the Python 3 virtual
+                        environment, deactivate the environment:</p>
+
+                        <pre>deactivate</pre>
+                    </div>
                 </section>
 
                 <section id="setting-up-the-os-build-environment">
diff --git a/static/main.css b/static/main.css
index 80ce0f2e..28e73dc1 100644
--- a/static/main.css
+++ b/static/main.css
@@ -329,6 +329,27 @@ main.normalize {
     margin: 0;
 }
 
+.notice {
+    border-radius: 12px;
+    border: 1px solid #74777f /* outline */;
+    background-color: #dae2f9 /* secondary container */;
+    color: #121c2b /* on secondary container */;
+    padding: 1em;
+    margin-block: 1em;
+}
+
+.notice-heading {
+    margin-block-start: 0;
+}
+
+.notice-heading::before {
+    content: "ⓘ ";
+}
+
+.notice pre {
+    margin-block-end: 0;
+}
+
 /* latin */
 @font-face {
     font-family: Roboto;
@@ -467,4 +488,10 @@ main.normalize {
     var {
         color: #ffb4ab;
     }
+
+    .notice {
+        border-color: #8e9099 /* outline */;
+        background-color: #3e4758 /* secondary container */;
+        color: #dae2f9 /* on secondary container */;
+    }
 }