Please fix this issue. It makes editing documents with a Linux based workstation very frustrating. 

Please fix this. This hurts Confluence adoption at a linux-heavy shop. It cannot be that hard.

This bug is very annoying. It started catching me when we upgraded Confluence from 5.9.6 to 6.5.2. Worked fine before.

I'm very interested in seeing a fix as it's made using Confluence a pain!

Let me know if I can provide any additional information or do any testing.

A possible workaround may be to first capture the contents of the paste buffer before overwriting it, then restoring that content after hijacking it.

This is still causing me to scream at Confluence in surprise and frustration every time it catches me out, which is not pleasant for my co-workers.
Why is the editor hijacking the paste buffer like this?

This seems to be related to Confluence (ab)using the middle-click paste buffer as an edit buffer when manipulating page contents.
Many actions, but particularly undo and switching from view to edit, cause the entire contents of the page to be inserted into that buffer, providing a nasty surprise when you paste what you thought was the text that you swipe-copied from somewhere else. The larger the page, the nastier the surprise when the entire page is unexpectedly inserted into itself, leaving the user to cancel the edit, re-click on Edit, then make the same edits again and try to remember to swipe-copy just before pasting, and not a single action earlier.

This isn't specific to Chrome; it's been causing havoc for me in Firefox.

Any word on a fix for this? As Mike Hudson said in January, this is fixed in TinyMCE. If this is the editor that Confluence uses, will it be included in future versions soon?

I'm on Confluence 5.6.6 and still seeing the bug.

This also annoyed me enough to look up a fix. After reading the above I tracked what happens to my clipboards through the sequence of operations with a little utility I wrote:

--- CHANGED: PRIMARY (action taken: double-click word to copy)
Formats: TIMESTAMP,TARGETS,MULTIPLE,SAVE_TARGETS,UTF8_STRING,COMPOUND_TEXT,TEXT,STRING,text/plain;charset=utf-8,text/plain
'userPrincipalName'

--- CHANGED: PRIMARY (action taken: middle-click Confluence )
Formats: TIMESTAMP,TARGETS,MULTIPLE,SAVE_TARGETS,UTF8_STRING,COMPOUND_TEXT,TEXT,STRING,text/plain;charset=utf-8,text/plain
'\xef\xbb\xbf\xef\xbb\xbf'

--- CHANGED: PRIMARY (action taken: double-click word to copy)
Formats: TIMESTAMP,TARGETS,MULTIPLE,SAVE_TARGETS,UTF8_STRING,COMPOUND_TEXT,TEXT,STRING,text/plain;charset=utf-8,text/plain
'sAMAccountType'

--- CHANGED: CLIPBOARD  (action taken: Ctrl-Shift-C to copy to clipboard)
Formats: TIMESTAMP,TARGETS,MULTIPLE,SAVE_TARGETS,UTF8_STRING,COMPOUND_TEXT,TEXT,STRING,text/plain;charset=utf-8,text/plain
'sAMAccountType'

--- CHANGED: PRIMARY (action taken: Ctrl-V to paste into Confluence)
Formats: TIMESTAMP,TARGETS,MULTIPLE,SAVE_TARGETS,UTF8_STRING,COMPOUND_TEXT,TEXT,STRING,text/plain;charset=utf-8,text/plain
'\xef\xbb\xbf\xef\xbb\xbf'

To be certain, it today, affects our version Confluence 5.6.1