commit	dee39e0926915213ccb6722a7e24b8ac7288bd87	[log] [tgz]
author	Josh Bleecher Snyder <josharian@gmail.com>	Thu May 29 14:25:08 2025 +0000
committer	Josh Bleecher Snyder <josharian@gmail.com>	Thu May 29 12:50:41 2025 -0700
tree	e487922e47a18eb94b13ac9e2212e7652f776e0f
parent	2d08119c97f1a909ba4f17827aee31aa98b8b2e7 [diff]

webui: fix chat timeline scrolling to reach exact bottom

Implement robust scroll-to-bottom behavior with retry logic to handle
dynamic content rendering and ensure chat view scrolls completely to
the bottom when browser windows are opened.

The issue occurred when popping browser windows - the chat timeline
would scroll toward the bottom but not reach the exact bottom position,
leaving some content (like the input field) partially visible or cut off.

Root cause analysis:
- 50ms timeout insufficient for dynamic content (images, tool cards) to render
- scrollHeight calculation happened before final layout was complete
- smooth scroll behavior could be interrupted by subsequent layout changes
- 1px tolerance in scroll detection too strict for various screen sizes

Implementation improvements:

1. Enhanced scrollToBottom() method:
   - Switch from 'smooth' to 'instant' scroll behavior for reliability
   - Calculate exact target scroll position (scrollHeight - clientHeight)
   - Add null safety checks for scroll container

2. New scrollToBottomWithRetry() method:
   - Retry logic with up to 5 attempts at 50ms intervals
   - Verify actual scroll position after each attempt
   - Continue retrying until exactly at bottom or max attempts reached
   - Prevents race conditions with dynamic content loading

3. Improved scroll detection accuracy:
   - Increased tolerance from 1px to 3px for isAtBottom detection
   - Better handling of fractional pixel differences across browsers
   - More reliable detection of 'pinToLatest' vs 'floating' states

4. Enhanced timing and integration:
   - Increased initial timeout from 50ms to 100ms for content rendering
   - Updated both automatic scroll (on message changes) and manual scroll (jump-to-latest button)
   - Consistent behavior across all scroll triggers

Technical benefits:
- Eliminates incomplete scrolling that left content partially visible
- Handles dynamic content loading (images, expanding tool cards, etc.)
- Provides immediate feedback with instant scroll behavior
- Self-correcting through retry mechanism for timing edge cases
- Better cross-browser compatibility with increased tolerance

Testing verification:
- Started test sketch instance and verified complete scroll behavior
- Confirmed chat scrolls to exact bottom showing input field fully
- Verified manual 'jump to latest' button works correctly
- Screenshots show complete message content and input accessibility

This ensures users always see the complete conversation and can easily
access the input field when browser windows are opened, resolving the
reported incomplete scrolling behavior.

Co-Authored-By: sketch <hello@sketch.dev>
Change-ID: sa9a8755f69c688cfk

webui/src/web-components/sketch-timeline.ts[diff]

1 file changed

tree: e487922e47a18eb94b13ac9e2212e7652f776e0f

README.md

Sketch

Sketch is an agentic coding tool. It draws the 🦉

🚀 Overview

Sketch runs in your terminal, has a web UI, understands your code, and helps you get work done. To keep your environment pristine, sketch starts a docker container and outputs its work onto a branch in your host git repository.

Sketch helps with most programming environments, but Sketch has extra goodies for Go.

📋 Quick Start

go install sketch.dev/cmd/sketch@latest
sketch

🔧 Requirements

Currently, Sketch runs on macOS and Linux. It uses Docker for containers.

Platform	Installation
macOS	`brew install colima` (or Docker Desktop/Orbstack)
Linux	`apt install docker.io` (or equivalent for your distro)
WSL2	Install Docker Desktop for Windows (docker entirely inside WSL2 is tricky)

The sketch.dev service is used to provide access to an LLM service and give you a way to access the web UI from anywhere.

🤝 Community & Feedback

Discord: Join our community at https://discord.gg/6w9qNRUDzS
GitHub Issues: Submit feedback at https://github.com/boldsoftware/sketch/issues

📖 User Guide

Getting Started

Start Sketch by running sketch in a Git repository. It will open your browser to the Sketch chat interface, but you can also use the CLI interface. Use -open=false if you want to use just the CLI interface.

Ask Sketch about your codebase or ask it to implement a feature. It may take a little while for Sketch to do its work, so hit the bell (🔔) icon to enable browser notifications. We won't spam you or anything; it will notify you when the Sketch agent's turn is done, and there's something to look at.

How Sketch Works

When you start Sketch, it:

Creates a Dockerfile
Builds it
Copies your repository into it
Starts a Docker container with the "inside" Sketch running

This design lets you run multiple sketches in parallel since they each have their own sandbox. It also lets Sketch work without worry: it can trash its own container, but it can't trash your machine.

Sketch's agentic loop uses tool calls (mostly shell commands, but also a handful of other important tools) to allow the LLM to interact with your codebase.

Getting Your Git Changes Out

Sketch is trained to make Git commits. When those happen, they are automatically pushed to the git repository where you started sketch with branch names sketch/*.

Finding Sketch branches:

git branch -a --sort=creatordate | grep sketch/ | tail

The UI keeps track of the latest branch it pushed and displays it prominently. You can use standard Git workflows to pull those branches into your workspace:

git cherry-pick $(git merge-base origin/main sketch/foo)

or merge the branch

git merge sketch/foo

or reset to the branch

git reset --hard sketch/foo

Ie use the same workflows you would if you were pulling in a friend's Pull Request.

Advanced: You can ask Sketch to git fetch sketch-host and rebase onto another commit. This will also fetch where you started Sketch, and we do a bit of "git fetch refspec configuration" to make origin/main work as a git reference.

Don't be afraid of asking Sketch to help you rebase, merge/squash commits, rewrite commit messages, and so forth; it's good at it!

Reviewing Diffs

The diff view shows you changes since Sketch started. Leaving comments on lines adds them to the chat box, and, when you hit Send (at the bottom of the page), Sketch goes to work addressing your comments.

Connecting to Sketch's Container

You can interact directly with the container in three ways:

Web UI Terminal: Use the "Terminal" tab in the UI
SSH: Look at the startup logs or click the information icon to see a command like ssh sketch-ilik-eske-tcha-lott. We have automatically configured your SSH configuration to make these special hostnames work.
Visual Studio Code: Look for a command line or magic link behind the information icon, or when Sketch starts up. This starts a new VSCode session "remoted into" the container. You can edit the code, use the terminal, review diffs, and so forth.

Using SSH (and/or VSCode) allows you to forward ports from the container to your machine. For example, if you want to start your development webserver, you can do something like this:

# Forward container port 8888 to local port 8000
ssh -L8000:localhost:8888 sketch-ilik-epor-tfor-ward go run ./cmd/server

This makes http://localhost:8000/ on your machine point to localhost:8888 inside the container.

Using Browser Tools

You can ask Sketch to browse a web page and take screenshots. There are tools both for taking screenshots and "reading images", the latter of which sends the image to the LLM. This functionality is handy if you're working on a web page and want to see what the in-progress change looks like.

❓ FAQ

"No space left on device"

Docker images, containers, and so forth tend to pile up. Ask Docker to prune unused images and containers:

docker system prune -a

🛠️ Development

See CONTRIBUTING.md for development guidelines.

📄 Open Source

Sketch is open source. It is right here in this repository! Have a look around and mod away.

If you want to run Sketch entirely without the sketch.dev service, you can set the flag -skaband-addr="" and then provide an ANTHROPIC_API_KEY environment variable. (More LLM services coming soon!)