Description can't exceed 255 characters - Custom Fields (Cloud)

If you attempt to add any custom field to a screen that has a long description, you might receive the following warning:

That is an imposed hard limit of 255 characters. Given the structure of the JSON that defines the Multi-Level Cascading Select field's values within an issue, the actual number of characters available for the value is slightly less than 255, depending on the complexity of your option's configuration.

A workaround to this is to shorten the text of the description. Refer to this issue to learn more: https://confluence.atlassian.com/jirakb/description-can-t-exceed-255-characters-custom-fields-1252008428.html.