25/01/2025: Thanks to the hint by another reviewer, I downloaded the xpi file for 6.0.0.4 from the previous versions at mozilla.org. I visited about:debugging#/runtime/this-firefox and used the "temporary load" feature. Works, but the trick needs to be reapplied everytime I restart Firefox (or the laptop of course). Note that the Chrome extension seems to work OK with no fiddling required, tested with Chromium on Ubuntu. At least in my experience, raindrop is much slower than diigo, that's the reason I accept the current issue with Diigo.

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I'm updating this on 12th of June 2024. It is broken on Firefox since version 6.0.0.5resigned1, dated 25/04/2024. The backend still works though. The Chrome extension still works too. 6.0.0.4 was dated 2017. My guess/hope is that it's just a matter of signing again the extenstion, for the author. Crossing fingers... because until it broke, it was one of my favourite tools, and I was a paying customer for the premium tier for many years.

For reference, around 2019, I wrote "The ability to highlight text as I browse Web pages is the cornerstone of my productivity and sanity. I highlight bits of texts and, so doing, I build summaries of interesting stuff, with bookmarks to the pages. So simple and super effective."

Long time user here. Extremely useful addon but the firefox version needs some more constant love... kinda feels second to chrome.

有些網站無法使用附加元件加入書籤，必須手動輸入。

Could you please clarify why do you need to access googleapi data , account.google data and clipboard data?
As specified by an other comment i'm worried about my privacy and I could'nt find any decent technical explications about why do you need those new permissions..
I saw that you're now able to read pdf files from Google Drive so I understanf it's linked but what do you have access exactly? Is it possible to deactivate this option?
I'm not upgrading until I do not have clear and sound answers.

It has been very useful and easy to use. But recently the new version of this add-on has become too intrusive and suspicious for my liking. It asks for 3 new permission: 1 .Access my google api data, 2. Access my google account data, and 3. Change my clipboard content. So I had to disable that update, and keep the old version. When this version expires, I will just completely remove the add-on.

An essential update, but like some of the other older Diigo add ons, ie Opera's the extension just buffers in the top right corner, never getting round to adding the bookmark. Please update!