Coder/deepseek-harness
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

feat(web): draw the sidebar's scrollbar only under the pointer

Browse Source 
The session list overflows after a handful of sessions, and its scrollbar
was drawn permanently in a column that is at rest most of the time.

SidebarRoot now tracks the pointer over the whole column and rebinds
ui-theme's scrollbar indirection pair to `transparent` while it is
outside, keeping the thumb for 2s after the pointer leaves so it does not
blink out on the way past. Rebinding colour leaves the list's
`scrollbar-gutter: stable` reservation in force, so revealing the bar
moves no row.

ui-theme's gate now states the widened contract: a rebind targets an -l2
token pair or `transparent`, and nothing else.
This commit is contained in:
creatixchu
2026-08-04 15:05:32 +08:00
parent 3c436d781e
commit a030397aca
20 changed files with 430 additions and 28 deletions
Download Patch File Download Diff File Expand all files Collapse all files

2
packages/client/ui-theme/README.md
View File

@@ -6,7 +6,7 @@ Theme plugin: ThemeService over the --dsw-* token base stylesheets (static scale
`src/styles/` holds five sheets, all imported by the web shell's `base.css`: `base.css`, `design-platform.css`, `scrollbar.css`, `gradient-shadow-text.css`, and `shiki.css`. `scrollbar.css` is the sole consumer of the `--dsw-alias-scrollbar-*` tokens and must follow `design-platform.css`, which declares them.
Scrollbar rebinding contract: `scrollbar.css` binds `--dsh-scrollbar-thumb` and `--dsh-scrollbar-thumb-hover` on `body` to the l1 (base-surface) tokens, and both rendering paths read that pair. An elevated surface (menu, popover, dialog) sets `--dsh-scrollbar-thumb: var(--dsw-alias-scrollbar-bg-l2)` and `--dsh-scrollbar-thumb-hover: var(--dsw-alias-scrollbar-hover-l2)` on its own container; one rebind retints whichever path the engine took.
Scrollbar rebinding contract: `scrollbar.css` binds `--dsh-scrollbar-thumb` and `--dsh-scrollbar-thumb-hover` on `body` to the l1 (base-surface) tokens, and both rendering paths read that pair. An elevated surface (menu, popover, dialog) sets `--dsh-scrollbar-thumb: var(--dsw-alias-scrollbar-bg-l2)` and `--dsh-scrollbar-thumb-hover: var(--dsw-alias-scrollbar-hover-l2)` on its own container; one rebind retints whichever path the engine took. The pair's other legal target is `transparent`, which draws no thumb at all — [ui-sidebar](../ui-sidebar/README.md) rebinds its column that way while the pointer is elsewhere. A rebind to the l1 pair is not a rebind; it restates the base-surface default.
The two paths are mutually exclusive by construction. `scrollbar-width`/`scrollbar-color` sit inside `@supports not selector(::-webkit-scrollbar)` because a non-`auto` value of either makes Chromium and Safari discard every `::-webkit-scrollbar*` rule for that element, `::-webkit-scrollbar-thumb:hover` included — declaring both unconditionally leaves `--dsh-scrollbar-thumb-hover` with no rendering anywhere. Firefox therefore takes the standard properties and WebKit-based engines take the pseudo-elements, so the hover token only ever renders through the pseudo-element path. Reasoning and the measured computed values: [the scrollbar Agent Note](../../../.agents/notes/implemented/bug-fix/2026-07-28-themed-scrollbars-and-reserved-gutter.md).