An Adobe Commerce Developer has created a new custom block extending
\Magento\Framework\view\Element\AbstractBlock and has set the cache_lifetime data property for the block so that the output gets cached.
The block is inserted into the sidebar, and displays differing content depending on which currency is being used. The developer finds that the block is displaying the same content for all currencies, depending on which currency is viewed first after the cache has been flushed.
How would the developer resolve this?