More information about Dropbox sync in Overleaf is available at: Dropbox Synchronization Once linked, any changes to your project in Overleaf will automatically sync to your Dropbox folder on your computer, and any changes you make locally in Dropbox will appear in your project online. A user with a premium subscription can link their Overleaf account to Dropbox. Overleaf provides an automatic two-way sync between Overleaf and Dropbox. Note that it is not currently possible to use the Overleaf-hosted web editor whilst offline, as all compilations are run on our servers. To ensure you can run all of the packages of Overleaf 'out-of-the-box', you can download the TeXLive distribution, and you can compile with Latexmk to compile everything in one go (see this article for more information on how Overleaf compiles your projects).

You can see some options for installing LaTeX here. You can use any plain text editor to edit your projects locally, and you can download a free installation of LaTeX to compile your projects locally as well. Overleaf provides a number of integrations which enable you to create and sync local copies of your projects, so that you can work offline using local text editors, and can keep these copies in sync with Overleaf when you're back online.

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