Why Ctrl+V won't paste images in Claude Code on WSL, with a fix

Summary

tl;dr Use Claude Code in WSL inside Windows Terminal? Copying an image in Windows and pressing Ctrl+V in Claude Code doesn't work. Three things break: (1) WSL only hands Windows images to the Linux side in an old BMP format Claude Code can't read; (2) WSL also keeps quietly overwriting your fixes a moment later; (3) Windows Terminal grabs Ctrl+V before Claude Code can see it. The fix is a small Windows program that converts the image to PNG, a Linux script that puts it on the Linux clipboard (and re-asserts once after WSL overwrites it), and one extra keybinding for Claude Code so the keystroke actually reaches the program. Copy an image in Windows. Open Claude Code inside a WSL terminal launched from Windows Terminal. Press Ctrl+V. Nothing happens. Three small things between the Windows clipboard and Claude Code’s chat input are broken. Each one is harmless on its own. Together they make image paste fail completely. Here’s what they are and the workaround I built until the upstream fixes catch up. What’s actually broken 1. The Windows-to-Linux clipboard sync only knows about an ancient image format WSL has a built-in piece called WSLg (the “g” is for graphics). Its job is to make Windows and the Linux side share things — including the clipboard, so copy-paste works across the boundary. For text, it works fine. For images, it does two things badly. First, it only syncs images in one direction: from Windows to Linux. Anything copied from a Linux app doesn’t flow back to Windows as an image. Second, when WSLg sends a Windows image over to Linux, it converts it into a single, dated format — a specific old BMP variant that uses an obscure colour encoding (“BI_BITFIELDS”). Most software’s BMP readers can’t handle it. Claude Code’s reader is one of those. It tries to read what arrives, gets nothing useful, and gives up — silently. No error, no toast, no visible failure. The image just doesn’t attach. (This is a known bug: claude-code#50552.) 2. The same Windows-to-Linux s...