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fix: drop regex lookbehind in GFM autolink to fix legacy-WebKit white screen - #27
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mdast-util-gfm-autolink-literal@2.0.1 uses a lookbehind assertion in its email autolink regex. Legacy WebKit engines (Safari < 16.4, e.g. the WKWebView on macOS 12) cannot compile lookbehind, and since regex literals compile at module parse time the whole frontend bundle failed to parse, rendering a blank screen in ACECode desktop. Patch the dependency to remove the lookbehind: findEmail already re-validates the preceding character at runtime via previous(match, true), so behavior is unchanged (covered by new regression tests). Also add scripts/check-regex-compat.mjs to the build so any future lookbehind regex literal in the bundle fails the build instead of blank-screening legacy WebKit users at runtime.
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lookbehind 从 pnpm patch 去掉是对症的：legacy WebKit 在 parse 阶段就编译 regex literal，单条就能让整个 bundle 白屏。findEmail 里现有的 previous(match, true) 能接住前置字符校验，7 个 autolink 回归用例也覆盖了常见边界。
check-regex-compat.mjs 扫 dist/index.html 在这个仓库里是成立的：vite-plugin-singlefile 把 JS 全部 inline 进 html。pnpm build 后挂这个检查能挡住以后新的 lookbehind。
顺带：PR 描述里写了 agent_browser_host_mac.mm 的 LOG_* 括号修复，但这两个 commit 里没有这个文件。不影响本次修复。
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Summary
(?<=...)(frommdast-util-gfm-autolink-literal@2.0.1's email autolink pattern). Lookbehind requires Safari 16.4+, but on macOS 12 the WKWebView / JavaScriptCore engine is pinned to Safari 15.6. The whole bundle failed to parse at load time, React never mounted, and the desktop main window rendered a white screen. Chrome (much newer engine) rendered normally, confirming the engine-version gap.mdast-util-gfm-autolink-literal@2.0.1. ThefindEmailcallback already runs a runtimeprevious(match, true)check that validates the preceding character, so dropping the lookbehind keeps valid email autolinking identical while letting the bundle compile on Safari 15.6-class engines.web/src/lib/gfmAutolinkCompat.test.js(7 cases) andweb/scripts/check-regex-compat.mjs, wired intopnpm buildto fail the build if anydistregex literal still uses lookbehind.src/desktop/agent_browser_host_mac.mmhad 10LOG_*macro calls whose bracedjson{...}argument was being split on commas. Parenthesized the argument so the macOS desktop target compiles. (Required to actually ship the rebuilt desktop app on macOS.)Test plan
pnpm install && pnpm buildinweb/— passes the regex-compat check.new Function(bundle)syntax check passes on macOS 12 (noInvalid regular expression).Impact / follow-ups
mdast-util-gfm-autolink-literalis upgraded past the lookbehind usage.