Ghost cursor appears at top-left (0,0) on initialization

[mats16]

Description

When initializing a Terminal instance, a ghost cursor is rendered at the top-left corner (coordinates 0,0) in addition to the actual cursor position. This cursor persists and doesn't disappear even when the terminal receives content.

Steps to Reproduce

1. Create a new Terminal instance with cursor enabled
2. Call terminal.open(container)
3. Observe that a cursor appears at the top-left corner (0,0)
4. The ghost cursor remains even after terminal content is rendered

Expected Behavior

Only one cursor should be visible at the actual cursor position, not at (0,0).

Actual Behavior

Two cursors are visible:

1. The correct cursor at the actual position
2. A ghost cursor at the top-left corner (0,0)

Root Cause Analysis

After investigating the minified source code, the issue appears to be in CanvasRenderer:

1. Initialization: lastCursorPosition is initialized to { x: 0, y: 0 } (around line 1337)
2. Rendering: The cursor rendering logic at line 1561-1578 checks g === 0 && I.visible && this.cursorVisible && this.renderCursor(I.x, I.y)
3. Problem: When the cursor moves to a new position, the old position (0,0) is not properly cleared, leaving a ghost cursor

Workaround

TBD

Environment

• ghostty-web version: 0.4.0
• Browser: Chrome (tested)
• OS: macOS

Suggested Fix

The CanvasRenderer should either:

1. Not render the cursor until a valid position is set
2. Properly clear the initial (0,0) position when the cursor moves
3. Initialize lastCursorPosition to a sentinel value that prevents initial rendering

[tnhu]

I got the same problem. Back and forth with Claude Code for a while, it does not know how to fix. I inspect and realize it's the 1x1 textarea that Ghost renders. Set both background and text color of this textarea to transparent would solve it nicely.

[frixaco]

Setting caret-color to transparent (or container's background color) on the container you use for the terminal seems to be a valid workaround.