copy-on-select = clipboard ONLY copies text as mixed types (html & plain) - would like to control this

[mbentley]

Issue Description

Sorry if this should be considered to be more of a feature instead of a bug. I'm not sure if this is anticipated behavior or not. When using copy-on-select = clipboard, if the selection I have in the clipboard is formatted, it's being copied as html.

$ osascript -e 'clipboard info'
«class utf8», 15, «class HTML», 262, «class ut16», 32, string, 15, Unicode text, 30

Copying the same text when using iTerm2, I get it copied as plain text:

$ osascript -e 'clipboard info'
«class utf8», 19, «class ut16», 40, string, 19, Unicode text, 38

This is problematic because in some applications, such as Obsidian or other apps that can paste rich text, you get unexpected output while I would always like plain text to be copied from a terminal application.

Expected Behavior

I would like to be able to control the ability to copy as plain text.

It would be great if this could be controlled in a similar fashion to:

keybind = copy=copy_to_clipboard:plain
keybind = super+c=copy_to_clipboard:plain

When copying using super+c with the above config, it copies as expected:

mb003071@H0K41KXDQP ~/L/A/com.mitchellh.ghostty ❯ osascript -e 'clipboard info'
«class utf8», 15, «class ut16», 32, string, 15, Unicode text, 30

You can also see it pastes as I would expect in my example using Obsidian to paste:

It would be ideal if the same control could be done for copying on select

I believe this was added in #9397

Actual Behavior

There is no setting that controls whether what is copied is HTML or plain (or mixed) to the best of my understanding.

Reproduction Steps

1. Open Ghostty
2. Go to a directory where you have some color formatted text - a symlink does it for me
3. Try to copy the text on select and have it set to clipboard
4. See that it pastes as mixed format (case use osascript -e 'clipboard info' to see this).

Here is an example where I am copying the text config.ghostty@ where there is different formatting. The different formatting is key for where the paste pastes funny:

Here is an example of it pasting funny in an app where it's adding extra lines (this is Obsidian but it also happens in other things like when pasting text into the Claude web interface, for example):

Ghostty Logs

n/a

Ghostty Version

Ghostty 1.3.1

Version
  - version: 1.3.1
  - channel: stable
Build Config
  - Zig version   : 0.15.2
  - build mode    : .ReleaseFast
  - app runtime   : .none
  - font engine   : .coretext
  - renderer      : renderer.generic.Renderer(renderer.Metal)
  - libxev        : kqueue

OS Version Information

macOS Tahoe 26.5.1

(Linux only) Display Server

None

(Linux only) Desktop Environment/Window Manager

No response

Minimal Ghostty Configuration

copy-on-select = clipboard

Additional Relevant Configuration

Just in case it is relevant, I use bash + starship in my terminal.

I acknowledge that:

• I have reviewed the FAQ and confirm that my issue is NOT among them.
• I have searched the Ghostty repository (both open and closed Discussions and Issues) and confirm this is not a duplicate of an existing issue or discussion.
• I have checked the "Preview" tab on all text fields to ensure that everything looks right, and have wrapped all configuration and code in code blocks with a group of three backticks (```) on separate lines.

[mbentley]

Just for proof of concept purposes, I have been testing locally just to verify that what I am seeing is indeed happening and I did a quick feature (which might not be the best way to implement this if it were to be adopted as a feature) to add a config option to allow me to configure the copy-on-select to be plain (also in https://github.com/mbentley/ghostty/tree/copy-on-select-plain):

diff --git a/src/Surface.zig b/src/Surface.zig
index c56c9791c..8b21dd3e1 100644
--- a/src/Surface.zig
+++ b/src/Surface.zig
@@ -301,6 +301,7 @@ const DerivedConfig = struct {
     clipboard_paste_bracketed_safe: bool,
     clipboard_codepoint_map: configpkg.Config.RepeatableClipboardCodepointMap,
     copy_on_select: configpkg.CopyOnSelect,
+    copy_on_select_format: input.Binding.Action.CopyToClipboard,
     right_click_action: configpkg.RightClickAction,
     middle_click_action: configpkg.MiddleClickAction,
     confirm_close_surface: configpkg.ConfirmCloseSurface,
@@ -380,6 +381,7 @@ const DerivedConfig = struct {
             .clipboard_paste_bracketed_safe = config.@"clipboard-paste-bracketed-safe",
             .clipboard_codepoint_map = try config.@"clipboard-codepoint-map".clone(alloc),
             .copy_on_select = config.@"copy-on-select",
+            .copy_on_select_format = config.@"copy-on-select-format",
             .right_click_action = config.@"right-click-action",
             .middle_click_action = config.@"middle-click-action",
             .confirm_close_surface = config.@"confirm-close-surface",
@@ -2373,7 +2375,7 @@ fn setSelectionAndCopy(self: *Surface, sel: terminal.Selection) !void {
         .clipboard => try self.copySelectionToClipboards(
             sel,
             &.{ .standard, .selection },
-            .mixed,
+            self.config.copy_on_select_format,
         ),

         // The selection clipboard is set if supported, otherwise the standard.
@@ -2385,7 +2387,7 @@ fn setSelectionAndCopy(self: *Surface, sel: terminal.Selection) !void {
             try self.copySelectionToClipboards(
                 sel,
                 &.{clipboard},
-                .mixed,
+                self.config.copy_on_select_format,
             );
         },
     }
diff --git a/src/config/Config.zig b/src/config/Config.zig
index 66b8c6057..a7177d78a 100644
--- a/src/config/Config.zig
+++ b/src/config/Config.zig
@@ -2419,6 +2419,20 @@ keybind: Keybinds = .{},
     else => .false,
 },

+/// The clipboard format used when copying text via `copy-on-select`.
+///
+/// Valid values:
+///
+///   * `mixed` - Copy as both plain text and HTML, allowing the receiving
+///     application to choose the appropriate format. This is the default.
+///   * `plain` - Copy as plain text only. Use this to prevent applications
+///     from receiving styled/HTML content when pasting.
+///   * `vt` - Copy with ANSI escape sequences preserved.
+///   * `html` - Copy as HTML only.
+///
+/// The default value is `mixed`.
+@"copy-on-select-format": inputpkg.Binding.Action.CopyToClipboard = .mixed,
+
 /// The action to take when the user right-clicks on the terminal surface.
 ///
 /// Valid values:

[hung0702]

I'm also hitting this issue. When using copy-on-select, terminal line breaks completely collapse and fuse text together when pasting into web browsers and text areas.

@mbentley's proposal sounds good to me!

[AMMullan]

This appears to be the likely culprit for #10741 also. No idea why Ghostty would copy as HTML by default - definitely like the idea suggested by @mbentley 💯

[zhiland]

Same here on macOS, pasting into Microsoft Teams. copy-on-select always includes the text/html flavor with no way to opt out.

Context on why this started: #9418 added a format parameter to the copy_to_clipboard keybind and changed its default to mixed (text/plain + text/html). The keybind can now be set to
copy_to_clipboard:plain, but copy-on-select never got a format argument, so it always takes the styled path. The original issue #9397 actually said the default with no format should stay
plain for backwards compatibility.

The HTML is emitted as <div style="...white-space: pre;"> with raw \n and no <br>, so apps that drop that CSS (Teams, being Electron) collapse every newline onto one line. Obsidian gets
unexpected rich text for the same reason.

Proposal (same as OP): let copy-on-select take a format, or add a separate option, defaulting to plain to match #9397's original intent.

(Closed my #13339 as duplicate of #12971)

[AMMullan]

Ah yay, nice research @zhiland - it's useful to know we can create a temporary workaround for it until it (hopefully) becomes a configurable setting (because most of us wouldn't want HTML to be a thing by default).

Have added this to my keybindings file:

keybind = performable:cmd+c=copy_to_clipboard:plain

Works a charm :)

[guiambros]

Same on NixOS. Copy-on-select from ghostty and pasting on Claude web and some other sites garbles all newlines, due to the default (and un-modifiable) being html.

The keybind = performable:cmd+c=copy_to_clipboard:plain serves as a workaround for now, but requires selecting the text and CTRL+C, thus making the copy-on-select useless.

Really hoping to see a configurable copy-on-select = clipboard:<format> soon.

[psionicalpha]

Hey folks, I'm relatively new to ghostty, however I've been experimenting with different terminals as of late and generally found that I really like this one. I seemingly, however, this very problem. I'm a debian + gnome desktop user, and I pretty habitually use both keyboard shortcuts and middle mouse click to paste. I've added this to the config file which solves the keyboard shortcut issue

keybind = ctrl+shift+c=copy_to_clipboard:plain

but middle mouse button is still doing the mix format messages and essentially pasting garbage into text fields that don't support it.

I'm going to see about integrating @mbentley 's suggestion on a custom compiled version to get around this for now, but would love to see this added officially.