Unsupported input

The tool may reject input that does not match the expected content, structure, or file type.

Fix: Confirm the tool input requirements and paste the correct type of data.

Incomplete values

Missing fields or partial content can block processing or produce weak results.

Fix: Provide the full required input before running the tool.

Copying placeholder content

Sample or placeholder values can lead to output that looks valid but is not ready for real use.

Fix: Replace placeholders with your actual values before relying on the result.

Does Markdown Preview highlight matches in real time?

Yes. Matches are highlighted as you type, and the match count plus capture groups update on every keystroke. For very long inputs, highlighting is debounced to keep typing responsive.

What diff algorithm does Markdown Preview use?

Markdown Preview uses the same Myers diff algorithm that git uses under the hood, so the output lines up with what you'd see in a git diff. Line-level and character-level modes are both available.

Can I save sessions in Markdown Preview?

Inputs are persisted to your browser's local storage between reloads — you can close the tab and come back to the same regex or input later. The data stays on your device.

Does Markdown Preview support multi-line mode and flags?

Yes. All standard JavaScript regex flags — g, i, m, s, u, y — are exposed as checkboxes in the UI, and the flag string is included when you copy the pattern.

Can I export matches from Markdown Preview?

Matches can be exported as JSON (one object per match with index, value, and capture groups), CSV, or a raw list. The export respects the current flags and input.