There is a certain limit of items that can be exported. It could vary depending on the browser, it's version, the operating system, so there is no specific number to be stated. The reason is that the file is generated completely client side, so we have to keep all of the data in memory until the generation is complete. A thing to check is that the Pako Deflate library is included to enable compression.
<!-- Load Pako ZLIB library to enable PDF compression -->
If that is the case and the export still fails, we do not recommend to use the built in client side exporting and implement server side export via 3rd party library instead.
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