Huge growth of bundle size after updating to v7

[dsaenko]

Hi!
We have problems with performance after updating @sentry/browser from 6.19.7 to 7.93.0 - increasing sentry chunk on ~50kb gzip. With version 6 we had ~23kb gzip, but now it's ~73kb gzip.

The cause of such drawdown in that we use Webpack Module Federation and specify @sentry/browser as shared module, so code of sentry is included to chunk fully, even if we don't use it. But with sentry v6 and absence of Replay it wasn't a problem.
The piece of our webpack configuration is below

new ModuleFederationPlugin({
    shared: {
	'@sentry/browser': {
        	eager: true,
                requiredVersion: packageJson.dependencies['@sentry/browser'],
                singleton: true
        },
        ...
    },
}),

Sentry Replay increases chunk on ~33kb gzip. I have tried to turn off Sentry Replay by sentryWebpackPlugin, but it reduced only 3kb

sentryWebpackPlugin({
	bundleSizeOptimizations: {
        	excludePerformanceMonitoring: true,
                excludeReplayIframe: true,
                excludeReplayShadowDom: true,
                excludeReplayWorker: true
	}
}),

And in total Sentry replay is still in the sentry chunk

We can't remove sentry from shared, because in that case we get even worse situation with performance, if count total size of javascript at the page.

Do you have any ideas how we can optimize that?

[AbhiPrasad]

Can you provide your Sentry.init file? It seems that webpack is bundling Replay even if you aren't using the integration. This means there is something faulty with your webpack setup. By default if you don't use the Replay integration it should be treeshaken out.

All our performance monitoring code also seems to be included even when the APIs are not being used.

[dsaenko]

Yes, our configuration is simple

import * as Sentry from '@sentry/browser';

Sentry.init({
    dsn: 'some_url',
    environment: 'some_env',
    release: 'some_release',
    sampleRate: 1
});

We don't define integrations at all, but Replay is off by default.

I also have tried to do integrations: [] in configuration, but it did't help to fix size of bundle.

By default if you don't use the Replay integration it should be treeshaken out.

Yes, it's true. And it works, if I remove sentry from shared section of Webpack Module Federation - sentry chunk becomes ~23kb gzip. But we can't do it, because we use microfrontends, and it's needed for better performance on pages with microfrontends.

Seems, the problem is on the side of combination new version of sentry with shared feature of Webpack Module Federation. But I have no idea more how fix this.

[AbhiPrasad]

But we can't do it, because we use microfrontends, and it's needed for better performance on pages with microfrontends.

This seems like an issue with Webpack Module Federation not treeshaking properly. I think you will have to adjust config there. There's nothing the Sentry package can do if module federation does not treeshake unused features.

[dsaenko]

I see. Thank you for the answer.