Why is 'postMessage' error showing when installing an app?

Shopify Apps
1

getiing below error in browser console

this error coming in browser console

Failed to execute ‘postMessage’ on ‘DOMWindow’: The target origin provided (‘’) does not match the recipient window’s origin (‘’).
?hmac=c3a3dfcc24aa98707a2cb006440c8ae9baf15bdc7b18cf205c60ca201fe41aa2&host=ZXBjaXQubXlzaG9waWZ5LmNvbS9hZG1pbg&shop=epcit.myshopify.com&timestamp=1657726346:35 Failed to execute ‘postMessage’ on ‘DOMWindow’: The target origin provided (‘https://epcit.myshopify.com’) does not match the recipient window’s origin (‘https://b4b1-49-205-146-229.ngrok.io’).

2

Which App is this? Can you share more details?

3

Hi @venkateshm383 ,

Please, share more details about the app and issues to get tips from me and other people here.

4

Hi,

This is custom app, I am trying to install app using custmized host,

I followed these steps

  1. I created custom app using cli 3

2, I would like create app using app url instead of using cli commands to show partner dashbaord preview mode

3, created app in partener dashboard

4, copied screet key and value to env file

  1. Restarted app using npm run serve under web folder of the app project

  2. When I try to select store and try install app I am getting the error which mentioned earlier

7, currently ruñing app in docker

How to fix this issue any steps I am missing

Same app able install using ngrok url when I run localy but when I run docker it failing to install

5

I am running app in docker

FROM node:18-alpine

ARG SHOPIFY_API_KEY
ENV SHOPIFY_API_KEY=$SHOPIFY_API_KEY
EXPOSE 8082
WORKDIR /app
COPY web .
COPY .env .
RUN npm install
RUN cd frontend && npm install && npm run build
CMD ["npm", "run", "serve"]

when I try install this app which running docker into my store , suddenly page comes up in ui then goes off it not installing , can help me out what could be the reason and how to fix