@daily-co/daily-js/README.md

Please check our [our documentation site](https://docs.daily.co/) to get started. If you're building a web app with our `daily-js` front-end JavaScript library, you may be particularly interested in:

# 🎥 Get started with Daily

Please check our [our documentation site](https://docs.daily.co/) to get started. If you're building a web app with our `daily-js` front-end JavaScript library, you may be particularly interested in:

- The [`daily-js` reference docs](https://docs.daily.co/reference#using-the-dailyco-front-end-library), for help adding video calls to your app
- The [REST API reference docs](https://docs.daily.co/reference), for help creating video call rooms, configuring features for those rooms, and managing users and permissions

# ⚠ Upcoming changes that may require action

## `strictMode`: false will no longer allow multiple call instances

Today, you can circumvent throwing an `Error` on creation of a second (or nth) Daily instance by setting `strictMode: false` in the constructor parameters. With the introduction of proper support for multiple instances, this is replaced with the opt-in parameter, `allowMultipleCallInstances`. So in a future release, if your application needs to use multiple call instances simultaneously, you must set this new parameter to `true`, otherwise multiple instances will not be allowed and an `Error` will be thrown (regardless of `strictMode`).

While we will technically support multiple instances and the fear of bugs when doing so goes away, the majority of use cases only requires one instance and having multiple is likely accidental and will still cause issues. It's for this reason we default to throwing an `Error` in the hopes of avoiding footguns.

Note: `strictMode`, which defaults to true, will continue to be used for disallowing use of a Daily call instance after it has been destroyed.

## `avoidEval` will become `true` by default

Today you can opt in to making `daily-js` behave in a CSP-friendly way by specifying `dailyConfig: { avoidEval: true }` wherever you provide your [call options](https://docs.daily.co/reference/daily-js/daily-iframe-class/properties). You can read more about this option and how to set up your CSP (Content Security Policy) in [this guide](https://docs.daily.co/guides/privacy-and-security/content-security-policy#custom-call-object).

Starting in an upcoming version of `daily-js`, `avoidEval` will switch to defaulting to `true`. To prepare for this change, please make sure that your CSP's `script-src` directive contains `https://*.daily.co` (or explicitly opt out of the new behavior by setting `avoidEval: false`).