Cmd+C for Copy does not work

[brother-darion]

When using Quick Look (Space) to preview .md files, I can select text but Cmd+C does not work. However, copying via the right-click context menu works fine. For other file types (e.g., .txt, .py, .pdf), Cmd+C works as expected.

[sbarex]

With which operating system? On macOS Tahoe it works normally. The app doesn't affect this aspect, which is managed automatically by the system.

[sensebat]

I can confirm the exact same behavior on macOS Tahoe 26.3 Beta.

I will attempt to replicate this bug on a fresh macOS Tahoe 26.2 now without Karabiner Elements installed.

[sensebat]

I just verified on a fresh install of macOS Tahoe 26.2. I used brew install --cask qlmarkdown followed by brew reinstall --no-quarantine --cask qlmarkdown.

Before I did this, I confirmed Command+C indeed works on a .txt file.

To reproduce the bug, I ran QLMarkdown.App once. Then went into quick look on this GitHub repo's README.md. You can see in the screenshot how the selection and the context menu looks

Marking the line breaks like this appears consistent with a .txt file. The "copy" button also looks consistent with the rest. However, a .txt preview has far more context menu options than QLMarkdown has:

I assume there was a misunderstanding above, hope this helps :)

[sbarex]

The copy-paste bug can't be my app's bug. What's actually displayed on the screen is an HTML file managed by the operating system.
The context menu for your screenshot is managed by macOS, and is in fact the same one that appears if you try to view an .html file.

[sensebat]

Hey thanks for the quick reply. GitHub issues are not about who is to blame. I just want to document unexpected behavior for posterity.

Upon attempting to copy from QuickLook on a downloaded .html file, this bug does not occur:

You can see from the screenshot that Safari is associated with .html files and I presume used to render the QuickLook. The context menu for .html files is identical for .md and .html files.

Have a good one :)

[Donglin5525]

I encountered a similar problem. Using CMD+C failed to copy, and a copy failure message appeared. However, the right-click copy function worked perfectly.