diff --git a/packages/app/src/pages/session/composer/session-question-dock.tsx b/packages/app/src/pages/session/composer/session-question-dock.tsx
index 35690030c9..03a66ea3a7 100644
--- a/packages/app/src/pages/session/composer/session-question-dock.tsx
+++ b/packages/app/src/pages/session/composer/session-question-dock.tsx
@@ -469,7 +469,9 @@ export const SessionQuestionDock: Component<{ request: QuestionRequest; onSubmit
         </>
       }
     >
-      <div data-slot="question-text">{question()?.question}</div>
+      <div data-slot="question-text" class="overflow-auto">
+        {question()?.question}
+      </div>
       <Show when={multi()} fallback={<div data-slot="question-hint">{language.t("ui.question.singleHint")}</div>}>
         <div data-slot="question-hint">{language.t("ui.question.multiHint")}</div>
       </Show>
diff --git a/packages/opencode/src/cli/cmd/tui/context/theme.tsx b/packages/opencode/src/cli/cmd/tui/context/theme.tsx
index 24d122162a..3829f4488c 100644
--- a/packages/opencode/src/cli/cmd/tui/context/theme.tsx
+++ b/packages/opencode/src/cli/cmd/tui/context/theme.tsx
@@ -773,7 +773,7 @@ function getSyntaxRules(theme: Theme) {
     {
       scope: ["extmark.paste"],
       style: {
-        foreground: theme.background,
+        foreground: selectedForeground(theme, theme.warning),
         background: theme.warning,
         bold: true,
       },
diff --git a/packages/opencode/src/cli/cmd/tui/feature-plugins/system/session-v2.tsx b/packages/opencode/src/cli/cmd/tui/feature-plugins/system/session-v2.tsx
index 5017b77b00..f9217ec403 100644
--- a/packages/opencode/src/cli/cmd/tui/feature-plugins/system/session-v2.tsx
+++ b/packages/opencode/src/cli/cmd/tui/feature-plugins/system/session-v2.tsx
@@ -30,6 +30,7 @@ import type {
   ToolTextContent,
 } from "@opencode-ai/sdk/v2"
 import { createEffect, createMemo, createSignal, For, Match, Show, Switch } from "solid-js"
+import { collapseToolOutput } from "../../util/collapse-tool-output"
 
 const id = "internal:session-v2-debug"
 const route = "session.v2.messages"
@@ -198,26 +199,28 @@ function UserMessage(props: { message: SessionMessageUser; index: number }) {
 
 function ShellMessage(props: { message: SessionMessageShell }) {
   const { theme } = useTheme()
+  const dimensions = useTerminalDimensions()
   const output = createMemo(() => stripAnsi(props.message.output.trim()))
   const [expanded, setExpanded] = createSignal(false)
-  const lines = createMemo(() => output().split("\n"))
-  const overflow = createMemo(() => lines().length > 10)
+  const maxLines = 10
+  const maxChars = createMemo(() => maxLines * Math.max(20, dimensions().width - 6))
+  const collapsed = createMemo(() => collapseToolOutput(output(), maxLines, maxChars()))
   const limited = createMemo(() => {
-    if (expanded() || !overflow()) return output()
-    return [...lines().slice(0, 10), "…"].join("\n")
+    if (expanded() || !collapsed().overflow) return output()
+    return collapsed().output
   })
   return (
     <BlockTool
       title="# Shell"
       spinner={!props.message.time.completed}
-      onClick={overflow() ? () => setExpanded((prev) => !prev) : undefined}
+      onClick={collapsed().overflow ? () => setExpanded((prev) => !prev) : undefined}
     >
       <box gap={1}>
         <text fg={theme.text}>$ {props.message.command}</text>
         <Show when={output()}>
           <text fg={theme.text}>{limited()}</text>
         </Show>
-        <Show when={overflow()}>
+        <Show when={collapsed().overflow}>
           <text fg={theme.textMuted}>{expanded() ? "Click to collapse" : "Click to expand"}</text>
         </Show>
       </box>
@@ -518,14 +521,15 @@ type ToolProps = {
 
 function GenericTool(props: ToolProps) {
   const { theme } = useTheme()
+  const dimensions = useTerminalDimensions()
   const output = createMemo(() => props.output?.trim() ?? "")
   const [expanded, setExpanded] = createSignal(false)
-  const lines = createMemo(() => output().split("\n"))
   const maxLines = 3
-  const overflow = createMemo(() => lines().length > maxLines)
+  const maxChars = createMemo(() => maxLines * Math.max(20, dimensions().width - 6))
+  const collapsed = createMemo(() => collapseToolOutput(output(), maxLines, maxChars()))
   const limited = createMemo(() => {
-    if (expanded() || !overflow()) return output()
-    return [...lines().slice(0, maxLines), "…"].join("\n")
+    if (expanded() || !collapsed().overflow) return output()
+    return collapsed().output
   })
   return (
     <Show
@@ -539,11 +543,11 @@ function GenericTool(props: ToolProps) {
       <BlockTool
         title={`# ${props.part.name} ${input(props.input)}`}
         part={props.part}
-        onClick={overflow() ? () => setExpanded((prev) => !prev) : undefined}
+        onClick={collapsed().overflow ? () => setExpanded((prev) => !prev) : undefined}
       >
         <box gap={1}>
           <text fg={theme.text}>{limited()}</text>
-          <Show when={overflow()}>
+          <Show when={collapsed().overflow}>
             <text fg={theme.textMuted}>{expanded() ? "Click to collapse" : "Click to expand"}</text>
           </Show>
         </box>
@@ -702,15 +706,17 @@ function BlockTool(props: {
 
 function Bash(props: ToolProps) {
   const { theme } = useTheme()
+  const dimensions = useTerminalDimensions()
   const output = createMemo(() => stripAnsi((stringValue(props.metadata.output) ?? props.output ?? "").trim()))
   const command = createMemo(() => stringValue(props.input.command) ?? pendingInput(props.part))
   const title = createMemo(() => `# ${stringValue(props.input.description) ?? "Shell"}`)
   const [expanded, setExpanded] = createSignal(false)
-  const lines = createMemo(() => output().split("\n"))
-  const overflow = createMemo(() => lines().length > 10)
+  const maxLines = 10
+  const maxChars = createMemo(() => maxLines * Math.max(20, dimensions().width - 6))
+  const collapsed = createMemo(() => collapseToolOutput(output(), maxLines, maxChars()))
   const limited = createMemo(() => {
-    if (expanded() || !overflow()) return output()
-    return [...lines().slice(0, 10), "…"].join("\n")
+    if (expanded() || !collapsed().overflow) return output()
+    return collapsed().output
   })
   return (
     <Switch>
@@ -719,12 +725,12 @@ function Bash(props: ToolProps) {
           title={title()}
           part={props.part}
           spinner={props.part.state.status === "running"}
-          onClick={overflow() ? () => setExpanded((prev) => !prev) : undefined}
+          onClick={collapsed().overflow ? () => setExpanded((prev) => !prev) : undefined}
         >
           <box gap={1}>
             <text fg={theme.text}>$ {command()}</text>
             <text fg={theme.text}>{limited()}</text>
-            <Show when={overflow()}>
+            <Show when={collapsed().overflow}>
               <text fg={theme.textMuted}>{expanded() ? "Click to collapse" : "Click to expand"}</text>
             </Show>
           </box>
diff --git a/packages/opencode/src/cli/cmd/tui/routes/session/index.tsx b/packages/opencode/src/cli/cmd/tui/routes/session/index.tsx
index ce651fdbe4..e8e29a40c9 100644
--- a/packages/opencode/src/cli/cmd/tui/routes/session/index.tsx
+++ b/packages/opencode/src/cli/cmd/tui/routes/session/index.tsx
@@ -84,6 +84,7 @@ import { UI } from "@/cli/ui.ts"
 import { useTuiConfig } from "../../context/tui-config"
 import { nextThinkingMode, reasoningTitle, useThinkingMode, type ThinkingMode } from "../../context/thinking"
 import { getScrollAcceleration } from "../../util/scroll"
+import { collapseToolOutput } from "../../util/collapse-tool-output"
 import { TuiPluginRuntime } from "@/cli/cmd/tui/plugin/runtime"
 import { DialogRetryAction } from "../../component/dialog-retry-action"
 import { SessionRetry } from "@/session/retry"
@@ -1696,12 +1697,12 @@ function GenericTool(props: ToolProps<any>) {
   const ctx = use()
   const output = createMemo(() => props.output?.trim() ?? "")
   const [expanded, setExpanded] = createSignal(false)
-  const lines = createMemo(() => output().split("\n"))
   const maxLines = 3
-  const overflow = createMemo(() => lines().length > maxLines)
+  const maxChars = createMemo(() => maxLines * Math.max(20, ctx.width - 6))
+  const collapsed = createMemo(() => collapseToolOutput(output(), maxLines, maxChars()))
   const limited = createMemo(() => {
-    if (expanded() || !overflow()) return output()
-    return [...lines().slice(0, maxLines), "…"].join("\n")
+    if (expanded() || !collapsed().overflow) return output()
+    return collapsed().output
   })
 
   return (
@@ -1716,11 +1717,11 @@ function GenericTool(props: ToolProps<any>) {
       <BlockTool
         title={`# ${props.tool} ${input(props.input)}`}
         part={props.part}
-        onClick={overflow() ? () => setExpanded((prev) => !prev) : undefined}
+        onClick={collapsed().overflow ? () => setExpanded((prev) => !prev) : undefined}
       >
         <box gap={1}>
           <text fg={theme.text}>{limited()}</text>
-          <Show when={overflow()}>
+          <Show when={collapsed().overflow}>
             <text fg={theme.textMuted}>{expanded() ? "Click to collapse" : "Click to expand"}</text>
           </Show>
         </box>
@@ -1871,14 +1872,16 @@ function BlockTool(props: {
 function Shell(props: ToolProps<typeof ShellTool>) {
   const { theme } = useTheme()
   const pathFormatter = usePathFormatter()
+  const ctx = use()
   const isRunning = createMemo(() => props.part.state.status === "running")
   const output = createMemo(() => stripAnsi(props.metadata.output?.trim() ?? ""))
   const [expanded, setExpanded] = createSignal(false)
-  const lines = createMemo(() => output().split("\n"))
-  const overflow = createMemo(() => lines().length > 10)
+  const maxLines = 10
+  const maxChars = createMemo(() => maxLines * Math.max(20, ctx.width - 6))
+  const collapsed = createMemo(() => collapseToolOutput(output(), maxLines, maxChars()))
   const limited = createMemo(() => {
-    if (expanded() || !overflow()) return output()
-    return [...lines().slice(0, 10), "…"].join("\n")
+    if (expanded() || !collapsed().overflow) return output()
+    return collapsed().output
   })
 
   const workdirDisplay = createMemo(() => {
@@ -1902,14 +1905,14 @@ function Shell(props: ToolProps<typeof ShellTool>) {
           title={title()}
           part={props.part}
           spinner={isRunning()}
-          onClick={overflow() ? () => setExpanded((prev) => !prev) : undefined}
+          onClick={collapsed().overflow ? () => setExpanded((prev) => !prev) : undefined}
         >
           <box gap={1}>
             <text fg={theme.text}>$ {props.input.command}</text>
             <Show when={output()}>
               <text fg={theme.text}>{limited()}</text>
             </Show>
-            <Show when={overflow()}>
+            <Show when={collapsed().overflow}>
               <text fg={theme.textMuted}>{expanded() ? "Click to collapse" : "Click to expand"}</text>
             </Show>
           </box>
diff --git a/packages/opencode/src/cli/cmd/tui/util/collapse-tool-output.ts b/packages/opencode/src/cli/cmd/tui/util/collapse-tool-output.ts
new file mode 100644
index 0000000000..da8d739351
--- /dev/null
+++ b/packages/opencode/src/cli/cmd/tui/util/collapse-tool-output.ts
@@ -0,0 +1,13 @@
+export function collapseToolOutput(output: string, maxLines: number, maxChars: number) {
+  const lines = output.split("\n")
+  if (lines.length <= maxLines && Array.from(output).length <= maxChars) {
+    return { output, overflow: false }
+  }
+
+  const preview = lines.slice(0, maxLines).join("\n")
+  if (Array.from(preview).length > maxChars) {
+    return { output: Array.from(preview).slice(0, Math.max(0, maxChars - 1)).join("") + "…", overflow: true }
+  }
+
+  return { output: [...lines.slice(0, maxLines), "…"].join("\n"), overflow: true }
+}
diff --git a/packages/ui/src/components/message-part.css b/packages/ui/src/components/message-part.css
index 0dd02d8129..78d574d8a1 100644
--- a/packages/ui/src/components/message-part.css
+++ b/packages/ui/src/components/message-part.css
@@ -935,7 +935,7 @@
     gap: 6px;
     margin-top: 12px;
     padding: 1px 1px 8px;
-    flex: 1;
+    flex-shrink: 0;
     min-height: 0;
     overflow-y: auto;
     scrollbar-width: none;
diff --git a/packages/ui/src/components/message-part.tsx b/packages/ui/src/components/message-part.tsx
index 07b8022abe..acf0c9dee3 100644
--- a/packages/ui/src/components/message-part.tsx
+++ b/packages/ui/src/components/message-part.tsx
@@ -58,6 +58,30 @@ import { animate } from "motion"
 import { useLocation } from "@solidjs/router"
 import { attached, inline, kind } from "./message-file"
 
+async function writeClipboard(text: string): Promise<boolean> {
+  const body = typeof document === "undefined" ? undefined : document.body
+  if (body) {
+    const textarea = document.createElement("textarea")
+    textarea.value = text
+    textarea.setAttribute("readonly", "")
+    textarea.style.position = "fixed"
+    textarea.style.opacity = "0"
+    textarea.style.pointerEvents = "none"
+    body.appendChild(textarea)
+    textarea.select()
+    const copied = document.execCommand("copy")
+    body.removeChild(textarea)
+    if (copied) return true
+  }
+
+  const clipboard = typeof navigator === "undefined" ? undefined : navigator.clipboard
+  if (!clipboard?.writeText) return false
+  return clipboard.writeText(text).then(
+    () => true,
+    () => false,
+  )
+}
+
 function ShellSubmessage(props: { text: string; animate?: boolean }) {
   let widthRef: HTMLSpanElement | undefined
   let valueRef: HTMLSpanElement | undefined
@@ -1064,9 +1088,10 @@ export function UserMessageDisplay(props: { message: UserMessage; parts: PartTyp
   const handleCopy = async () => {
     const content = text()
     if (!content) return
-    await navigator.clipboard.writeText(content)
-    setState("copied", true)
-    setTimeout(() => setState("copied", false), 2000)
+    if (await writeClipboard(content)) {
+      setState("copied", true)
+      setTimeout(() => setState("copied", false), 2000)
+    }
   }
 
   const revert = () => {
@@ -1490,9 +1515,10 @@ PART_MAPPING["text"] = function TextPartDisplay(props) {
   const handleCopy = async () => {
     const content = text()
     if (!content) return
-    await navigator.clipboard.writeText(content)
-    setCopied(true)
-    setTimeout(() => setCopied(false), 2000)
+    if (await writeClipboard(content)) {
+      setCopied(true)
+      setTimeout(() => setCopied(false), 2000)
+    }
   }
 
   return (
@@ -1834,9 +1860,10 @@ ToolRegistry.register({
     const handleCopy = async () => {
       const content = text()
       if (!content) return
-      await navigator.clipboard.writeText(content)
-      setCopied(true)
-      setTimeout(() => setCopied(false), 2000)
+      if (await writeClipboard(content)) {
+        setCopied(true)
+        setTimeout(() => setCopied(false), 2000)
+      }
     }
 
     return (