error TS2484: Export declaration conflicts with exported declaration of 'JSX'.

Today, due to the performance issue I am having with my ionic/firebase mobile app, I decided to upgrade from ionic 4 to ionic 5. I was feeling lucky, so I just ran the following command and hoped everything just works.

npm i @ionic/angular@latest –save

Of cause it didn’t just work. When I tried to compile my app, I got the error in the title. I searched around and didn’t find anything. But I suspect it has something to do with my Angular being outdated. So I found this upgrade guide. I ran the following command in sequence and updated Angular. It fixed the issue!

npm install -g @angular/cli

ng update @angular/cli@8 @angular/core@8 --allow-dirty

The popup has been closed by the user before finalizing the operation.

I am working on my Ionic/Firebase mobile app. Suddenly I couldn’t login using Google Sign-In. It would close the sign in window and throw this error in the console. It turned out that has something to do with the Chrome settings in Incognito mode. So I guess I won’t be using Incognito mode for now. You can see more discussion here.