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Lightning Web Components (LWC) is a programming model used to build custom HTML elements. These custom elements, the web components, are made using HTML and modern JavaScript. Because of this, LWC is an efficient way to add high-performing custom elements. LWC is an open-source technology. Like any other Javascript framework (example: Angular, React), Pulsar can run custom HTML/JS apps written in LWC even when offline as long as they are using the data layer API Pulsar provides.

For more information about Lightning Web Components, refer to https://developer.salesforce.com/docs/component-library/documentation/en/lwc/lwc.get_started_introduction.

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For more information about Lightning Data Server, refer to https://developer.salesforce.com/docs/component-library/documentation/en/lwc/lwc.data_ui_api.

Do LWC

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apps using LDS work with Pulsar in offline mode?

Unless Salesforce decides to open-source the Lightning Data Service, only Salesforce can run both the apps using Lightning Web Components and the Lightning Data Service at this time. This means that you must be online to update pages using these technologies. They may work offline with the cached data for SF or SFS Mobile, but they will not work with Pulsarwithin Pulsar if you are offline since the LDS framework is not available because it’s not published for integration by Salesforce.

If you have an LWC app that can be published as a link/URL, it certainly can be accessed within Pulsar by launching in a webview when you are online.