Though you've explained about the WT engine and its limits with ToolTips, here's what I could glean from a brave search (FWIW):
In general software or web-based interfaces, tooltip cutoffs are often caused by CSS properties such as overflow: hidden on parent containers, which clips content that extends beyond the element's boundaries. Adjusting the overflow property to visible or ensuring the tooltip container dynamically resizes to fit its content can resolve this. For instance, in a CSS tooltip, if the parent element restricts overflow, the tooltip text may be cut off unless the overflow is explicitly set to visible.
Additionally, in some cases, specific characters like commas or semicolons in the tooltip text can cause truncation in certain editors, such as the Buff Editor in Warcraft III, where text is cut at the first comma or semicolon. This behavior may be due to how the engine parses the string, and the workaround is to avoid using such punctuation or restructure the text.
In summary, tooltip cutoffs are typically due to either hard limits in the engine, CSS overflow settings, or parsing issues with special characters. Solutions involve adjusting the content structure, modifying CSS rules, or using engine-specific configuration options.
PS: Do you have a list hidden within WT itself of all the ToolTips?