Microsoft/vscode

Markdown Image Hover Preview broken for file paths exceeding 259

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#261880 opened on Aug 15, 2025

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 (5 comments) (0 reactions) (1 assignee)TypeScript (74,848 stars) (10,221 forks)batch import
bughelp wanted

Description

Type: Bug

While editing a markdown file, hovering the cursor over the link to an image should popup a preview of the image. However, if the path to the image exceeds 259 characters the preview does not appear in the popup, and instead displays the broken image link icon. The markdown preview window renders the image regardless of path length.

Steps to reproduce

  1. Create a markdown file and open in the VSCode editor.
  2. Insert a link to an image file where the path is over 259 characters.
  3. Hover your curser over the link, and the broken link icon appears (see first image below).
  4. Open the markdown preview pane and note that the image is displayed as expected (see first image below).
  5. shorten the path of the source image to be 259 characters or less.
  6. Hover your curser over the link, and image preview appears as expected (see second image below).

VS Code version: Code - Insiders 1.104.0-insider (0ab18bd00955d2a3d69eb66d8eea982b76a53780, 2025-08-15T10:51:05.286Z) OS version: Windows_NT x64 10.0.26100 Modes:

Item Value
CPUs Intel(R) Core(TM) Ultra 7 165H (22 x 3072)
GPU Status 2d_canvas: enableddirect_rendering_display_compositor: disabled_off_okgpu_compositing: enabledmultiple_raster_threads: enabled_onopengl: enabled_onrasterization: enabledraw_draw: disabled_off_okskia_graphite: disabled_offtrees_in_viz: disabled_offvideo_decode: enabledvideo_encode: enabledvulkan: disabled_offwebgl: enabledwebgl2: enabledwebgpu: enabledwebnn: disabled_off
Load (avg) undefined
Memory (System) 63.46GB (42.71GB free)
Process Argv --crash-reporter-id 95cb8fae-2bdd-4240-a0e6-b694852bf1a4
Screen Reader no
VM 0% 
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todos-0:31366869
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search_len1:31367733

Contributor guide

Tech stack
typescriptjavascriptnodejselectron
Domain
frontend
Issue type
bug
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
3
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
1-3 hours
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
blocked
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
clear
Prerequisites
Experience with VSCode codebaseTypeScriptNode.js
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
35
Research direction
Investigate the markdown image hover preview code in VS Code's markdown extension, likely in `extensions/markdown language features/`. The hover preview uses a different code path than the markdown preview pane. Look for constants or conditions that truncate or fail when paths exceed 259 characters. Check file system access code that constructs image URIs. Review comments in the issue for additional clues.