Apply Modern Theme in SharePoint Subscription Edition

You might be shocked, but many companies still use the SharePoint server version. If you are a proud owner of the SharePoint Server Subscription Edition, you should take advantage of the modern themes but can’t find the option to apply them.

After spending a few hours trying to figure out how to apply a modern theme to SharePoint Server Subscription Edition, I finally got it working. However, I had to use a browser console. I know it’s not a great option, but it’s better than no custom theme.

Prerequisites

Make sure to get a JSON from your theme. You can use the UI Fabric Theme Designer to create a theme. After you pick the primary color, go to Export > JSON and simply copy the JSON. You will need it later.

If you want to continue and apply a theme, you will need to be a site collection administrator on the target site.

Apply a theme using REST API via the browser console

• Open your SharePoint site
• Go to site content. It’s crucial for the next step.
• Open the browser console (browser dev tools) by pressing F12.
• Paste and run the following javascript code:

function RestRequest(url,params) {
  var req = new XMLHttpRequest();
  req.onreadystatechange = function ()
  {
    if (req.readyState != 4) // Loaded
      return;
    console.log(req.responseText);
  };
  // Prepend web URL to url and remove duplicated slashes.
  var webBasedUrl = (_spPageContextInfo.webServerRelativeUrl + "//" + url).replace(/\/{2,}/,"/");
  req.open("POST",webBasedUrl,true);
  req.setRequestHeader("Content-Type", "application/json;charset=utf-8");
  req.setRequestHeader("ACCEPT", "application/json; odata.metadata=minimal");
  req.setRequestHeader("x-requestdigest", _spPageContextInfo.formDigestValue);
  req.setRequestHeader("ODATA-VERSION","4.0");
  req.send(params ? JSON.stringify(params) : void 0);
}

var pal = {
    "palette" : {
      "themePrimary": "#1E479A",
      "themeLighterAlt": "#f3f6fb",
      "themeLighter": "#d0daef",
      "themeLight": "#aabce0",
      "themeTertiary": "#6483c2",
      "themeSecondary": "#2f57a5",
      "themeDarkAlt": "#1a3f8a",
      "themeDark": "#163574",
      "themeDarker": "#102756",
      "neutralLighterAlt": "#f8f8f8",
      "neutralLighter": "#f4f4f4",
      "neutralLight": "#eaeaea",
      "neutralQuaternaryAlt": "#dadada",
      "neutralQuaternary": "#d0d0d0",
      "neutralTertiaryAlt": "#c8c8c8",
      "neutralTertiary": "#bab8b7",
      "neutralSecondary": "#a3a2a0",
      "neutralPrimaryAlt": "#8d8b8a",
      "neutralPrimary": "#323130",
      "neutralDark": "#605e5d",
      "black": "#494847",
      "white": "#ffffff"
    }
}
RestRequest("/_api/thememanager/ApplyTheme", {name:"Corporate theme", themeJson: JSON.stringify(pal)});

As a result, the theme will be applied. You can verify it by going to the site settings > Change the look. You should see the “Current” theme you just applied.

Use REST API via PowerShell ❌ (Does not work)

I hoped to make it work with PnP PowerShell and the Invoke-PnPSPRestMethod method, but it didn’t.

Here is my unsuccessful attempt:

# UnInstall-Module SharePointPnPPowerShellOnline -Scope CurrentUser
Import-Module SharePointPnPPowerShellOnline
Connect-PnPOnline -Url http://spappdevse
# Define the theme properties
$themePalette = @{
    themePrimary       = "#1E479A";
    themeLighterAlt    = "#f3f6fb";
    themeLighter       = "#d0daef";
    themeLight         = "#aabce0";
    themeTertiary      = "#6483c2";
    themeSecondary     = "#2f57a5";
    themeDarkAlt       = "#1a3f8a";
    themeDark          = "#163574";
    themeDarker        = "#102756";
    neutralLighterAlt  = "#f8f8f8";
    neutralLighter     = "#f4f4f4";
    neutralLight       = "#eaeaea";
    neutralQuaternaryAlt = "#dadada";
    neutralQuaternary  = "#d0d0d0";
    neutralTertiaryAlt = "#c8c8c8";
    neutralTertiary    = "#bab8b7";
    neutralSecondary   = "#a3a2a0";
    neutralPrimaryAlt  = "#8d8b8a";
    neutralPrimary     = "#323130";
    neutralDark        = "#605e5d";
    black              = "#494847";
    white              = "#ffffff";
}

# Convert the theme properties to a JSON object
$themeJson = ConvertTo-Json $themePalette

# Create the payload for the REST request
$payload = @{
    name      = "Corporate theme";
    themeJson = $themeJson;
}
$payloadJson = ConvertTo-Json $payload


# Invoke the REST request. This will fail
Invoke-PnPSPRestMethod -Method Post -Url "/_api/thememanager/ApplyTheme" -Content $payloadJson

Please let me know if someone can make it work with PnP PowerShell!

Conclusion

This article will help you to apply a custom theme to SharePoint Server Subscription Edition.