gopalparashar421 · gopalparashar421 · Jun 21, 2026 · Jun 28, 2026 · Jun 29, 2026 · Jun 29, 2026
diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
@@ -15,7 +15,7 @@ jobs:
     name: build
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
 
       - name: Install uv
         uses: astral-sh/setup-uv@v7

diff --git a/.github/workflows/docs.yml b/.github/workflows/docs.yml
@@ -24,7 +24,7 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
 
       - name: Install uv
         uses: astral-sh/setup-uv@v7

diff --git a/.github/workflows/lint.yml b/.github/workflows/lint.yml
@@ -15,7 +15,7 @@ jobs:
     name: lint
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
 
       - name: Install uv
         uses: astral-sh/setup-uv@v7

diff --git a/.github/workflows/publish.yml b/.github/workflows/publish.yml
@@ -34,7 +34,7 @@ jobs:
       should_publish: ${{ steps.check-pypi.outputs.should_publish }}
       repository: ${{ steps.set-repo.outputs.repository }}
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
 
       - name: Install uv
         uses: astral-sh/setup-uv@v7
@@ -102,7 +102,7 @@ jobs:
     if: needs.version-check.outputs.should_publish == 'true'
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
 
       - name: Install uv
         uses: astral-sh/setup-uv@v7

diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
@@ -20,7 +20,7 @@ jobs:
         python-version: ["3.10", "3.11", "3.12"]
 
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
 
       - name: Install uv
         uses: astral-sh/setup-uv@v7

diff --git a/.gitignore b/.gitignore
@@ -16,6 +16,9 @@ pyrightconfig.json
 working/
 .zed/
 uv.lock
+/.cursor/agents
+/.cursor/reference
+/.cursor/skills
 /.github/agents
 /.github/reference
 /.github/skills

diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -6,6 +6,41 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 ---
 
+## [Unreleased]
+
+---
+
+## [1.4.0] — 2026-07-19
+
+### Added
+
+- **Responsive chart chrome** — legend, top bar, subchart tabs, and HTML tables scale typography (and table padding) with the embedded window size via shared CSS `clamp()` tokens (`--chrome-font-*`). Designed for roughly 480×320–2560×1440 windows at 1x/2x HiDPI. No new Python sizing knobs.
+- **`StreamChart.show_async(...)`** — asyncio-friendly server start that mirrors `Chart.show_async` (non-blocking `show` under the hood, then runs until cancelled).
+- **`Window.run_script(..., transient=False)`** — additive keyword used by `StreamChart` to classify per-bar data scripts; ignored by the pywebview `Chart` path.
+
+### Changed
+
+- **`legend(..., font_size=...)` removed** (**breaking**) — both `AbstractChart.legend` and `SeriesCommon.legend` no longer accept `font_size`. Legend type size is owned by CSS; pass content and optional `color` / `font_family` only. `layout(font_size=...)` and `watermark(font_size=...)` are unchanged (canvas/LWC, not chrome).
+- **Top bar and subchart tab overflow** — when widgets/tabs no longer fit at the responsive type-scale floor, the top bar and subchart tab bar scroll horizontally instead of clipping or compressing labels.
+- **`stream-shim.js` reconnect** — after an established session closes, the page `location.reload()`s for a fresh JS context (avoids duplicate `Lib.Handler` construction). Close code `4002` uses a short backoff retry instead of reload; reload attempts are bounded via `sessionStorage`.
+
+### Fixed
+
+- **StreamChart reconnect flood** — while disconnected, per-bar `series.update` / `setData` / marker scripts are no longer buffered. On (re)connect the server replays a bounded structural script log, then emits a data snapshot from authoritative Python state (`candle_data` / series `data` / markers / tracked whitespace), so reopen-after-hours no longer replays thousands of updates and crash the page.
+- **Candlestick snapshot** — main-series reconnect data is taken from `candle_data` (full OHLC), not the empty inherited `data` frame.
+- **Snapshot/live cutover** — `_ws` is set only after the snapshot is fully sent under the data guard, so bars streamed during handshake are not lost.
+- **`bulk_run` tagging** — transient vs structural tags are preserved through batched flushes; purely transient batches are dropped while disconnected.
+- **StreamChart CSP** — Content-Security-Policy now allows WebSocket connections (`connect-src 'self' ws: wss:`) and inline styles (`style-src 'self' 'unsafe-inline'`), so live streaming and chrome styling work under the default CSP header.
+- **StreamChart WebSocket scheme** — the browser shim picks `wss://` on HTTPS pages and `ws://` otherwise, instead of always using `ws://`.
+- **`StreamWindow` inheritance** — subclasses `Window` so shared helpers (`_id_gen`, tables, style) stay in sync with `AbstractChart`.
+- **Volume profile data helper** — internal data path aligned between Python and the TypeScript plugin.
+
+### Notes
+
+- **Snapshot boundary** — series data, markers, and whitespace from `append_whitespace` are snapshot-backed on reconnect. Other per-bar mutations (table cells, price lines, legend, PositionTool P&L) still buffer as structural and can grow if updated every bar.
+
+---
+
 ## [1.3.0] — 2026-06-19
 
 ### Added

diff --git a/README.md b/README.md
@@ -181,7 +181,7 @@ if __name__ == '__main__':
     chart.crosshair(mode='normal', vert_color='#FFFFFF', vert_style='dotted',
                     horz_color='#FFFFFF', horz_style='dotted')
 
-    chart.legend(visible=True, font_size=14)
+    chart.legend(visible=True)
 
     chart.set(df)
 
@@ -247,7 +247,7 @@ ___
 
 ### 7. StreamChart — browser-based chart over HTTP/WebSocket:
 
-`StreamChart` spins up a local FastAPI/Uvicorn server and streams data to any browser tab. No desktop window is required — ideal for headless servers, notebooks, or remote development.
+`StreamChart` spins up a local FastAPI/Uvicorn server and streams data to any browser tab. No desktop window is required — ideal for headless servers, notebooks, or remote development. On (re)connect it rebuilds from a data snapshot (not a backlog of every `update()` while the tab was closed).
 
 ```python
 import pandas as pd

diff --git a/docs/source/examples/subchart.md b/docs/source/examples/subchart.md
@@ -2,7 +2,8 @@
 
 Tabbed subcharts let you switch between multiple independent charts inside a
 single desktop window. Call `create_subchart()` on the main chart; a tab bar
-appears automatically above the charts on the first call.
+appears automatically above the charts on the first call. When there are more
+tabs than fit the window width, the tab bar scrolls horizontally.
 
 > **Note:** This is separate from the **Panes API** (`pane_index`, `add_pane()`),
 > which stacks multiple series vertically in one chart view. See

diff --git a/docs/source/reference/abstract_chart.md b/docs/source/reference/abstract_chart.md
@@ -319,9 +319,11 @@ ___
 
 
 
-```{py:method} legend(visible: bool, ohlc: bool, percent: bool, lines: bool, color: COLOR, font_size: int, font_family: str, text: str, color_based_on_candle: bool)
+```{py:method} legend(visible: bool, ohlc: bool, percent: bool, lines: bool, color: COLOR, font_family: str, text: str, color_based_on_candle: bool)
 
 Configures the legend of the chart.
+
+Legend type size is CSS-responsive (`clamp()` via shared chrome tokens). There is no Python `font_size` parameter — pass content and color/family only.
 ```
 ___
 
@@ -446,7 +448,7 @@ ___
 
 Creates a tabbed sub-chart inside the same webview window and returns a {py:class}`SubChart` instance.
 
-On the **first call**, a tab bar is injected above the charts and the main chart is assigned a tab labelled `main_label`. On subsequent calls `main_label` is ignored.
+On the **first call**, a tab bar is injected above the charts and the main chart is assigned a tab labelled `main_label`. On subsequent calls `main_label` is ignored. When tab labels exceed the available width, the tab bar scrolls horizontally.
 
 See the [Subcharts example](../examples/subchart.md).
 ```

diff --git a/docs/source/reference/series.md b/docs/source/reference/series.md
@@ -191,10 +191,11 @@ Shows a previously hidden series.
 ```
 ___
 
-```{py:method} legend(visible, lines, color, font_size, font_family, text, pane_index)
+```{py:method} legend(visible, lines, color, font_family, text, pane_index)
 
 Configures the legend for the pane this series lives on.
 
+Legend type size is CSS-responsive. There is no Python `font_size` parameter.
 ```
 ___
 

diff --git a/docs/source/reference/stream_chart.md b/docs/source/reference/stream_chart.md
@@ -25,18 +25,35 @@ Open the URL in any browser. The token is a one-time secret — keep it private.
 > **Tip:** the printed URL is a one-time CSRF-like token; do not expose it publicly.
 > To open the browser automatically, pass `open_browser=True` to `show()`.
 
+### Reconnect model
+
+While disconnected, per-bar data scripts are dropped (not buffered). On connect the
+server replays structural setup scripts, then a data snapshot from Python state
+(series OHLC/values, markers, tracked whitespace). Same-page reconnects reload the
+tab for a clean JavaScript context. See the [StreamChart tutorial](../tutorials/stream_chart.md)
+for the snapshot boundary.
+
 ___
 
 
-```{py:method} show(port: int, host: str, open_browser: bool, block: bool, cors_origins: list[str])
+```{py:method} show(port: int, host: str, open_browser: bool, block: bool, cors_origins: list[str], debug: bool)
 
 Starts the FastAPI/Uvicorn server and optionally opens the system browser.
+Returns the chart URL once the server is accepting connections.
 
 * `port` *(int, default 8080)*: TCP port to listen on.
 * `host` *(str, default "127.0.0.1")*: Bind address. Use `"0.0.0.0"` for LAN access (a security reminder is printed).
 * `open_browser` *(bool, default False)*: Open the default browser to the chart URL.
 * `block` *(bool, default True)*: Block the calling thread until Ctrl+C is received.
 * `cors_origins` *(list[str], optional)*: Additional allowed CORS origins (e.g. `"http://192.168.1.10:8080"`). `http://127.0.0.1` and `http://localhost` are always permitted.
+* `debug` *(bool, default False)*: Enable FastAPI debug mode.
+
+```
+
+```{py:method} show_async(port: int, host: str, open_browser: bool, cors_origins: list[str], debug: bool)
+
+Asyncio variant of `show`. Starts the server in a worker thread, returns the URL once
+ready, then awaits until the task is cancelled or interrupted.
 
 ```
 

diff --git a/docs/source/reference/tables.md b/docs/source/reference/tables.md
@@ -6,6 +6,8 @@ Tables are panes that can be used to gain further functionality from charts. The
 
 The `Table` and `Row` objects act as dictionaries, and can be manipulated as such.
 
+Table font size and header/cell padding scale responsively with the window via CSS (no Python `font_size` parameter). Colors, borders, text alignment, column widths, and sticky header positioning remain instance-driven as before.
+
 `width`/`height`
 : Either given as a percentage (a `float` between 0 and 1) or as an integer representing pixel size.
 

diff --git a/docs/source/reference/topbar.md b/docs/source/reference/topbar.md
@@ -22,6 +22,8 @@ Topbar widgets share common parameters:
 * `name`: The name of the widget which can be used to access it from the `topbar` dictionary.
 * `align`: The alignment of the widget (either `'left'` or `'right'` which determines which side of the topbar the widget will be placed upon.
 
+Chrome typography (button, switcher, textbox, menu labels) scales responsively with the embedded window size via CSS `clamp()` tokens. There is no Python font-size API for the top bar. When left and right widgets exceed the available width, the top bar scrolls horizontally (widgets do not shrink or wrap).
+
 ___
 
 

diff --git a/docs/source/tutorials/stream_chart.md b/docs/source/tutorials/stream_chart.md
@@ -94,6 +94,39 @@ if __name__ == '__main__':
         time.sleep(0.1)
 ```
 
+## Reconnect behavior
+
+While no browser is connected, per-bar data scripts (`setData` / `update` / markers)
+are **not** buffered. On (re)connect the server:
+
+1. Replays a bounded **structural** script log (series creation, styling, drawings, …).
+2. Emits a **data snapshot** from Python state (OHLC/volume, line series, markers,
+   and whitespace from `append_whitespace`).
+
+Reopening a tab after hours of disconnected streaming therefore loads from current
+state instead of replaying every bar update. Same-page reconnects reload the page
+so structural replay always targets a fresh JavaScript context.
+
+**Snapshot boundary:** table cells, price lines, legend text, and PositionTool P&L
+updated every bar still append to the structural log and can grow if you mutate
+them per bar while disconnected.
+
+## Asyncio
+
+Use `show_async` when the chart shares an event loop with other coroutines:
+
+```python
+import asyncio
+from lightweight_charts import StreamChart
+
+async def main():
+    chart = StreamChart()
+    chart.set(df)
+    await chart.show_async(port=8080, open_browser=True)
+
+asyncio.run(main())
+```
+
 ## Using plugins with StreamChart
 
 All plugins work identically with `StreamChart`:
@@ -117,6 +150,8 @@ chart.show(block=True)
 | Window | pywebview desktop window | Any browser via HTTP |
 | Display | Requires display server | Headless compatible |
 | Access URL | n/a | Printed one-time token URL |
-| `show()` signature | `show(block)` | `show(port, host, open_browser, block)` |
+| `show()` signature | `show(block)` | `show(port, host, open_browser, block, …)` |
+| `show_async()` | Yes | Yes |
+| Reconnect | n/a | Structural replay + data snapshot |
 | Screenshot | `chart.screenshot()` | Not supported |
 | `JupyterChart` | Yes | No |
diff --git a/examples/5_styling/styling.py b/examples/5_styling/styling.py
@@ -32,7 +32,7 @@
         horz_style="dotted",
     )
 
-    chart.legend(visible=True, font_size=14)
+    chart.legend(visible=True)
 
     chart.set(df)
 

diff --git a/lightweight_charts/__init__.py b/lightweight_charts/__init__.py
@@ -1,4 +1,4 @@
-__version__ = "1.3.0"
+__version__ = "1.4.0"
 
 from .abstract import (
     AbstractChart,
-Original file line number
+Diff line change
@@ Expand Up / @@ -22,6 +22,8 @@ Topbar widgets share common parameters: @@
     * `name`: The name of the widget which can be used to access it from the `topbar` dictionary.
     * `align`: The alignment of the widget (either `'left'` or `'right'` which determines which side of the topbar the widget will be placed upon.
+    Chrome typography (button, switcher, textbox, menu labels) scales responsively with the embedded window size via CSS `clamp()` tokens. There is no Python font-size API for the top bar. When left and right widgets exceed the available width, the top bar scrolls horizontally (widgets do not shrink or wrap).
     ___
@@ Expand Down @@