"Failed to copy to clipboard!" from tiddler opened in new window

#1

Hello,

In a single-file-based TiddlyWiki in Chrome, I was using the macro:

\define clipVariable()
<$wikify name=wikified-input text=<<variable_set_from_surrounding_list_widget>> output="text">
<$button message="tm-copy-to-clipboard" param=<<wikified-input>> > <<variable_set_from_surrounding_list_widget>> {{$:/core/images/copy-clipboard}}</$button>
</$wikify>
\end

This seems to work well in the main Story River. However, when I open the containing tiddler as a new window, I get the message “Failed to copy to clipboard!”.

I’ve tried to wrap the whole tiddler in a tiddler widget to give it the right context (something that helps in the sidebar) and removing the wikify widget to see if that was interfering … but no luck.

Anyone have an idea on what is failing here? Is this browser cross-window security intervening?

Thanks,
/Mike

#2

Can you try building up from one that does work rather than reducing from a broken one?

I was able to successfully copy to clipboard from this simplified variant, both from the StoryRiver and from an external window:

Clipboard Test.json (406 Bytes) (We need to save after importing it.)

I launched the window by right clicking on the link in the Recent tab and choosing “Open in new window”. Are you launching it differently? The difference could certainly be there.

#3

The tm-copy-to-clipboard message is handled in $:/core/modules/utils/dom.js by the exports.copyToClipboard function which uses document.execCommand("copy") to actually perform the clipboard copy action.

According to https://developer.mozilla.org/en-US/docs/Mozilla/Add-ons/WebExtensions/Interact_with_the_clipboard:

When opening a tiddler as a new window (via the more > open in new window command in the tiddler’s toolbar), the window’s “context” is “about:blank”, which is NOT considered to be a secure context. Thus, the exports.copyToClipboard code invoked from $:/core/modules/utils/dom.js fails, and throws an error, which is reported using text from $:/language/Notifications/CopiedToClipboard/Failed.

Note that, in contrast, when a tiddler is opened in a new window by right-clicking on the tiddler title and choosing “Open in new window” (as @Scott_Sauyet has done), the resulting window has the same “context” as the originating window. Thus, if the originating window uses https:// or file://, then so will the new window… and, since those are considered to be secure contexts, the tm-copy-to-clipboard function will succeed in the new window without throwing an error, which is reported using text from $:/language/Notifications/CopiedToClipboard/Succeeded.

TL/DR: yes, this is “browser cross-window security intervening”

-e

1 Like
#4

Thank you for the great explanation.

Never before have I used that link. I don’t think I’ve even //noticed// it!

Always more to learn.

#5

Thank you @EricShulman and @Scott_Sauyet .

I was actually opening the new window neither way.

The background reason I was opening a new window to view the tiddler was that I had a wide table that would spill over into the sidebar if opened in the Story River so I wanted it to have it’s own resizeable and scrollable window to make it easy to navigate and click a cell to copy it to clipboard. So I built a fake link (which happens to be displayed in the sidebar) via:

<$button message="tm-open-window" param="Wide Table Tiddler" class="tc-btn-invisible tc-tiddlylink" tooltip="Opens in new window to allow width">Open the Wide Table&nbsp;{{$:/core/images/open-window}}</$button>

It would seem that the tm-open-window message uses the same mechanism as more > open in new window so I was thwarted from doing something seemingly benign.

I guess I either have to figure out how to have a wide table in a tiddler not overflow into the sidebar (which might lead me to figure out how to keep the header row and column always visible while scrolling around) or see if a modal or popup window will suit my purposes.

As @Scott_Sauyet said, always more to learn.

Thanks for your help and explanation.
/Mike