Install the InDesign plugin

The Mestra panel runs inside InDesign. This page covers the install, sign-in and updates.

In the panel, brands are called Centres and flagged formats are marked Needs a look. On the web they are Brands and To check. They are the same things.

Requirements

Item	What you need
InDesign	Adobe InDesign 2025 (version 20.0) or later
Mestra account	An organisation, with you as an editor or owner. A viewer can’t connect apps.
The plugin file	`mestra-indesign.ccx`
Network	Access to `https://app.withmestra.com`. The panel contacts only that address.

Install

The plugin isn’t in the Adobe Exchange store yet. You download it from the Mestra web app.

In the Mestra web app, open Organisation > Apps and select Download for InDesign (.ccx). Anyone in your organisation can download it. The page shows the current version.
Double-click the file, or open it through Creative Cloud. Adobe’s installer adds Mestra to InDesign.
In InDesign, open Plugins → Mestra.

In the Mestra panel, press Sign in.
The panel shows Your code and opens your browser at the Mestra Connect page. If the browser can’t open, the panel shows a link to open yourself.
Check that the code matches. Choose your organisation, then press Allow.
The panel shows Signed in as your name and organisation.

The code lasts 10 minutes. If it expires, sign in again. Nobody copies or pastes a token. Sign out in the panel revokes the sign-in.

Permissions

The panel asks InDesign for these permissions.

Permission	Why
Network to `https://app.withmestra.com`	To plan layouts and sign in
Local file system (full access)	To save the .indd and PNG files
Launch process (`http`, `https`, `file`, and `.png` files)	To open the sign-in page and your exported files

Owners can see and sign out every InDesign sign-in on the Apps page in the web app. Everyone else sees only their own.

Updating

There is no update button in the panel. We email organisation owners when a new version is available. Download the new .ccx file from the Apps page and install the new file. If InDesign says Mestra is already installed, remove Mestra in Creative Cloud and install again.

Troubleshooting

Symptom	Cause	Fix
“Your role (viewer) can’t connect apps.”	You’re a viewer in that organisation.	Ask an owner to change your role. See Invite your team.
“The code expired. Sign in again.”	The 10-minute code ran out.	Press Sign in again.
“Sign-in was cancelled in the browser.”	Cancel was pressed on the Connect page.	Press Sign in and choose Allow.
“You’re signed out. Sign in again.”	The sign-in was revoked or ended.	Press Sign in again.
“Couldn’t sign in. Try again.”	The sign-in didn’t complete.	Try again. If it keeps happening, contact Support.
“InDesign isn’t accepting scripts right now”	A dialog is open, such as a missing links or fonts alert.	Close the dialog and try again.
A PNG doesn’t open from the panel on a Mac	The Mac won’t open a PNG from a panel directly.	The panel opens the PNG’s folder in the Finder. Open the file from there.

Still stuck? See Troubleshooting or Support.