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Tabs Outliner does not save tabs on Chrome exit if they does not contain any notes or if the window with them didn't have a custom title.

That's in theory. In practice there is a bug, and on Chrome exit tabs often become saved in the tree as crashed. But not always

I am not sure you are talking about this problem or about something else. I just tried with different Chrome versions - and i cannot reproduce situation when tab after being closed in Chrome still stay in the tree (if they not having any notes on self).

So if you have a sure step by step scenario to reproduce this problem please describe it. Also please mention your Chrome version and your OS.

Best Regards,
Vladyslav

PS If Tabs Outliner works and render the tree then the  database is 100% not corrupted or broken. Also if for any reason you need to contact me privately - my email is present in about (info) dialog in Tabs Outliner.
Yeh, plan to use IndieGoGo.
Thank's for a links
Interesting information about Wikipedia. Thanks.

The advice is good, i plan to try exactly this.
Preparing now a fundraising campaign.

must admit. problem is present again in recent Chrome builds, despite the tries to overcome it.

To spent on this more time need to have this time in a first place. There was expectation that donations will help to continue project development but they all failed.

Plan soon release a paid version with richer functionality. If sales will allow to continue
development then this free version will also be updated and problem will be fixed. I hope.

Yet worth to note that this problem does not affect core audience - tabs hoarders - they never close browser actually. So for them is more important the crash detection and window lost prevention functionality.

Unfortunately when Chrome become normally closed there is no way how this can be detected from extension, so from the extension point of view every close is a crash.

If somebody can invent simple way to distinguishe and remember normal Chrome close from crash i will be happy to integrate such fix. 
thanks for suggestion - i added this in the my internal todo list. Thought meantime i cannot promise when there will be done. But you are right, it's a good feature to have.

Next release will have a complete support for keyboard shortcuts, so it will be possible to delete tabs just by pressing Del, and move cursor by arrows keys - this might actually help in this case, as it is definitely a faster way to delete the tabs.
You can drag links from web pages directly in to the tree, they will be added as saved.
One other solution - open as much as you want and then just save the window immediately.

I use both methods quite often.
The sources is closed and will stay so most likely. The future versions and features planned to be paid (what is already implemented will stay as is - free). Donations (300$ for 2 years by the way if you interested) unfortunately does not cover even time spended on updates of this tool because of the continues Chrome changes. Opensourcing and giving away the tool will remove from me any possibility to continue its development, and there a lot of what i need and want to done in this tool.

Through you can easily find in the Chrome profile the text dumps of the tree in the JSON format. And add this folder to some cloud backup service. This files will be possible to import directly in the tree soon. Autobackup configured from extension directly to GoogleDrive will also be soon released.

Worth to note that you cannot write files from Chrome extension anywhere on disk. Only inside some special places in the Chrome profile - and this is already done.

Best,
Vladyslav
The problem is about TO memory usage.
On a 40 000 nodes for example TO really start to use a lot of RAM. There is already a fix for this. Plan to release it soon. RAM consumption will drop on a magnitude after this. Through It's all not relevant to users with only several thousand nodes.

As for Great Suspender - there is plans to integrate it more closely with TO. At least display the state of suspended by Great Suspender tabs and on restore restore saved items that was suspended before save, as not suspended. Is this sound good? I myself do not use Great Suspender but it's looks like this simple steps will make it more useful companion with TO - so any comments will be interesting to hear.

Unfortunately Chrome does not provide API to restore such state (for security reason as i understand, to not allow extensions manipulate this lists - why is there such paranoya between Chrome developers - i dont know, this feature is asked for years).

So, mission Impossible, through there already some development (not released meantime) that allow to view the tree in any point in the past (and so, access the old tab urls). Of course it's not as userfriendly as back-forward buttons.
Well, i think the best i can say is that the work is not abandoned.
Hope soon some more news you will see in the extension itself.