Update the doc on changing RHDH logo

Update the doc on changing RHDH logo

Author: GitHub Actions

modules/customizing-the-appearance/proc-customize-rhdh-branding-logo.adoc

@@ -5,9 +5,9 @@
 [id="proc-customize-rhdh-branding-logo_{context}"]
 = Customizing the branding logo of your {product-short} instance
 
-You can customize the branding logo of your {product-short} instance by configuring the `branding` section the `{my-app-config-file}` file, as shown in the following example:
+You can customize the branding logo of your {product-short} instance by configuring the `branding` section in the `{my-app-config-file}` file, as shown in the following example:
 
-[source,yaml]
+[source,yaml,subs="+quotes"]
 ----
 app:
   branding:
@@ -19,6 +19,21 @@ where:
 
 <1> `fullLogo` is the logo on the expanded (pinned) sidebar and expects a base64 encoded image.
 <2> `iconLogo` is the logo on the collapsed (unpinned) sidebar and expects a base64 encoded image.
++
+You can format the `BASE64_EMBEDDED_FULL_LOGO` environment variable as follows:
++
+[source,yaml,subs="+quotes"]
+----
+BASE64_EMBEDDED_FULL_LOGO: "data:image/svg+xml;base64,<file_base64>"
+----
++
+The following example demonstrates how to customize the `BASE64_EMBEDDED_FULL_LOGO` using the `data:image/svg+xml;base64,<file_base64>` format:
++
+[source,yaml,subs="+quotes"]
+----
+SVGLOGOBASE64=$(base64 -i logo.svg)
+BASE64_EMBEDDED_FULL_LOGO="data:image/svg+xml;base64,$SVGLOGOBASE64"
+----
 
 You can also customize the width of the branding logo by setting a value for the `fullLogoWidth` field in the `branding` section, as shown in the following example: