HTML.edit is not able to contain more than ~30K (29,996 characters) in a field. Documents can be larger than 30K when including the Header and Footer areas (and will export the complete contents of Header, Body and Footer), but imported documents will be truncated to 30K. Some functions also run into this 30K limit. If a future version of HyperCard allows for unlimited field lengths, I won't be the only one to breathe a sigh of relief.
In fact, I've pretty much run out of development room as well. Short of compiling all my scripts, if anyone wants a whole lot more HTML.edit features and larger documents, contact Apple Computer and try to talk them into increasing HyperCard's limits.
There is a file size indicator at the top right of the editor document window which displays the number of characters in the Header, Body and Footer sections. This indicator is updated on opening the document window, exiting the Header, Body or Footer areas, or clicking directly on the indicator text. It is in the format "H{header size}:B{body size}:F{footer size}".
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