Looking at http://en.wikipedia.org/wiki/ID3 I see that early versions of tags allowed only very limited amounts of data to be stored, but later versions remove these limits.
I notice for example that on podcasts I download from the BBC, Mp3tag shows Comment text that just stops in the middle of a word, even though I've widened the field as far as the display will let me do so.
I've just experimented by pasteing a long line of text - in repeated known-length chunks - into a Comment field. When I drag the Column View column boundary markers apart to widen the displayed size of the comment field there comes a point when the text I see just stops, followed by a small square. I cannot get the display to show me more than 260 bytes of comment text.
However if I hover the mouse over that field, a tooltip shows me that more text is being stored, but the amount shown is limited by the width of my computer's screen.
If I click on the field value, it gets highlighted and the screen view scrolls sideways to show me the rightmost set of characters in the comment text, showing that everything I originally pasted there is present. However I cannot then scroll the screen view leftwards to show the comment text that precedes the rightmost chunk. The cursor-left key will move the cursor from the righthand end of the displayed text back to the leftmost displayed character, and then vanishes (presumably onto earlier text) but the screen does not scroll to show the earlier text.
If I click & drag the scrollbar, I do see the earlier text but as soon as I click on an early part of the text, the app repositions the cursor at the righthand end of the entire text.
Is there any chance of this being fixed?
Alternately - and perhaps more usefully for very long pieces of text - is there any chance of such texts when you click on them to edit them being displayed in something more like a text editor (or webpage form) screen ie with wrapped lines? Even OLEing them to an external editor would make them much easier to view/edit.