Where does the bug appear (feature/product)?
Cursor IDE
Describe the Bug
In the Cursor Agent chat page, some KaTeX-rendered LaTeX formulas are parsed correctly but lose the visible stretchy delimiter glyphs.
Observed issues:
\sqrt{…} is parsed and partially rendered, but the left radical glyph is missing. The radicand and the top overline are visible.
Matrix delimiters are also missing. For example, pmatrix / bmatrix show the matrix entries but not the surrounding parentheses or brackets.
This does not appear to be a LaTeX syntax issue. DevTools confirms that the KaTeX annotation contains \sqrt, and the sqrt-related DOM is generated. However, the SVG/path or equivalent structure responsible for rendering the radical glyph is missing from the final DOM.
Steps to Reproduce
In Cursor Agent chat, ask the agent to output:
[
\sqrt{x^2+y^2}
]
Also test:
[
I_1 =
\int_0^{\pi}
\frac{\sin^2 x}{\sqrt{1+\cos^2 x}}
, dx
]
Matrix examples:
[
\begin{pmatrix}
a & b \
c & d
\end{pmatrix}
]
[
\begin{bmatrix}
a & b \
c & d
\end{bmatrix}
]
Expected Behavior
\sqrt{x^2+y^2} should display a complete radical sign, including the left radical glyph and the top overline.
pmatrix should display surrounding parentheses.
bmatrix should display surrounding square brackets.
Other stretchy delimiters such as \left…\right and cases should render normally.
Operating System
Windows 10/11
Version Information
Version: 3.5.38 (user setup)
VSCode Version: 1.105.1
Commit: 009bb5a3600dd98fe1c1f25798f767f686e14750
Date: 2026-05-26T21:32:06.537Z
Layout: editor
Build Type: Stable
Release Track: Default
Electron: 39.8.1
Chromium: 142.0.7444.265
Node.js: 22.22.1
V8: 14.2.231.22-electron.0
OS: Windows_NT x64 10.0.26100
Does this stop you from using Cursor
No - Cursor works, but with this issue