1870342 - Thumbnails cache from shortcuts (Tiles) -- even manually added ones -- gets cleared upon browser close, require re-download at every startup, if "Clear history when Nightly closes" is configured to clear browsing history

Status: REOPENED

(Firefox :: New Tab Page, defect)

Description

[careca]

Attachment: screenshot - 15122023-1849.jpg

User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:120.0) Gecko/20100101 Firefox/120.0

Steps to reproduce:

Open profile folder:
C:\Users%USERPROFILE%\AppData\Local\Mozilla\Firefox\Profiles\xxxxxxx.default-release\thumbnails
Open browser and let the thumbnails populate.
Select the options as per screenshot.
Close browser.
Check the previously opened folder.
In my case, all of the generated .png's are gone.
Next startup the browser repeats the process of populating the thumbnails.

Actual results:

Thumbnails (png files in that folder) are gone after browser is closed.

Expected results:

Browser should keep the files.

Comment 1

[careca]

Found out that the clearing of the folder is tied to the setting for clearing history: "Browsing & Downloading history".

Temporary fix is to set all the files inside the folder as read only, that way, they dont get deleted and next startup all tiles have their icons/images right away! No more waiting for download of each one! The way it should be out of the box.

Permanent fix is to change code to allow local icons/local path for the tiles or make the deletion of the thumbnails folder dependent on another setting like cache clearing, which would make more sense.

Comment 2

[Ina Popescu, Desktop QA]

I've tried to reproduce this issue in the latest Firefox 121.0.1 and Nightly 123.0a1 on Windows10 x64, but the thumbnails folder isn't populated while browsing. Have you changed any particular pref in about:config?
Can you reproduce your issue in Troubleshoot mode or using a new profile?

Comment 3

[careca]

Hi, thanks for response, i have changed some settings, but cant remember which.
May i ask, do you have any tiles with custom links/custom icons ?
Maybe the folder only exists if the user sets custom icons for tiles.

Comment 4

[Ina Popescu, Desktop QA]

Setting the component and waiting for the developer's opinion about it.
If this is not the correct component, please feel free to change it to a more appropriate one.

Comment 5

[Mike Conley (:mconley) (:⚙️)]

Hi careca,

Users rely on us removing all traces of user history when they configure Firefox to do so at any time (on demand, or on shutdown).

We include thumbnails in that set of data, since thumbnails are concrete pieces of data that indicate where a user has navigated on the web. Not clearing those thumbnails is an information leak, which is something we take very seriously.

So it's very much expected that we clear these thumbnails if the browser is configured to clear history on shutdown, or if the user decides to clear history at any moment. Unfortunately, this does mean regenerating those thumbnails on demand after they've been cleared.

Comment 6

[careca]

Hi Mark, i tried to explain it but maybe i couldn't pass on the information in the best way.
To reiterate, i am referring to the thumbnails created from custom links for tiles.
It has nothing to do with history, although one may say the browser had to retrieve the image from that custom link,at least once.
Can you see how it doesn't make sense to download everything, every restart?
Furthermore, the links for the icons are right there with the links in the pinned tiles, how does it configure a leak when the user sets it up himself?

Comment 7

[Mike Conley (:mconley) (:⚙️)]

REOPENING for now, since it sounds like there's some new information here that wasn't clear in the original description.

careca, you mentioned that you're seeing thumbnails for "custom links in tiles". Do you mean you're setting a custom image for some Top Sites (the rows of items directly beneath the search input), like these?:

https://i.imgur.com/elWjMzF.png

Comment 8

[careca]

Hi Mike, yes, yes! That's exactly what i meant to say.
I'm sorry im not very articulate, as english isn't my primary language.

Comment 9

[BugBot [:suhaib / :marco/ :calixte]]

The severity field is not set for this bug.
:amy, could you have a look please?

For more information, please visit BugBot documentation.

Comment 10

[careca]

Hi, this is still happening, i have to set the cached files as read-only so that they dont have to be constantly repopulated.
I am specificaly reffering to the png files that are cached to show up in the tiles in:
C:\Users\USER\AppData\Local\Mozilla\Firefox\Profiles\PROFILE.default-release\thumbnails

Comment 11

[careca]

Attachment: screenshot - 05022025-2023.bmp

Comment 12

[careca]

Attachment: screenshot - 05022025-2032.bmp

Comment 13

[BugBot [:suhaib / :marco/ :calixte]]

Redirect a needinfo that is pending on an inactive user to the triage owner.
:thecount, since the bug doesn't have a severity set, could you please set the severity or close the bug?

For more information, please visit BugBot documentation.

Comment 14

[careca]

Hi, still happening.

Comment 15

[careca]

Hi, a video showing the issue.

Video

Comment 16

[Daniel Holbert [:dholbert]]

Attachment: reporter's latest screencast

Comment 17

[Daniel Holbert [:dholbert]]

(In reply to careca from comment #15)

Hi, a video showing the issue.

(Posted as bugzilla attachment in comment 16, for convenience/persistence in case the proton.me link changes/disappears.)

Comment 18

[Daniel Holbert [:dholbert]]

I can reproduce. More-specific STR:
(1) Create a custom new-tab "shortcut-tile" with a custom image, i.e. where you provide the image-URL -- I'm using https://i.redd.it/6comsojb5fa31.png which happens to be a large PNG.

(2) Notice that the image that you provided appears in the thumbnails subdirectory in your Firefox profile folder.

(3) Visit Firefox preferences, about:preferences, and search for HIstory, and choose "Customize history" from the dropdown menu.

(4) Check the checkbox for "Clear history when Nightly closes", and click "Settings" below that.

(5) In the "Settings" dialog that appears, only check the box for "Browsing & download history"

(6) Quit Firefox, and check your thumbnails subdirectory again.

(7) Re-launch Firefox and watch your new-tab page and thumbnails subdirectory.

ACTUAL RESULTS:
In step 6, the custom-image disappears from the thumbnails subdirectory.
In step 7, the new-tab page initially loads with a blank custom-image and then after some time, the custom image appears.

EXPECTED RESULTS:
Probably there was no reason for that custom-image to disappear? It's a pinned entry on my new-tab page, not part of the browsing history that I requested to be cleared.

Note: if you repeat the STR but without the custom-image part, then when you relaunch Firefox, you end up with a placeholder favicon with just the first initial of the website title.

Comment 19

[Daniel Holbert [:dholbert]]

I suspect that as part of "clear browsing history", we're clearing the shortcut-tile image data for all user-generated shortcut tiles, and we're doing that because some of them may be auto-generated from the user's history. However, not all of them are dependent on the user's history -- when the user has taken the time to manually add certain shortcut tiles for their favorite sites , then it doesn't really make sense "clear browsing and download history" operations to clear those shortcut tiles' images.

Comment 20

[Daniel Holbert [:dholbert]]

Alternate STR, not requiring clear-on-close, which instead trigger a permanently-blank shortcut tile (for the rest of your session):

(1) Create a custom new-tab "shortcut-tile" with a custom image, i.e. where you provide the image-URL -- I'm using the derpfox PNG from mdauer's GitHub avatar: https://avatars.githubusercontent.com/u/173702880?v=4

(2) Open a new tab, ensure that the custom image shows up as-expected.

(3) Ctrl+Shift+Del (or Hamburger-menu | History | Clear Recent History). Choose When: Everything and ensure "Browsing & Download history" is checked. (the other checkboxes don't matter), and click "Clear".

(4) Hold "Shift" and reload the new-tab page (to do a "full" refresh). Note that the custom image is gone from your shortcut tile.

(5) Open a new tab, notice that the custom image is back.

(6) Open another new tab (as many as you like).

ACTUAL RESULTS:
The custom image is missing from your thumbnail tile in step 4 and 6 (though not in step 5, oddly).

EXPECTED RESULTS:
Custom image should not be missing. It probably shouldn't have been purged by clear-recent-history?

Comment 21

[Daniel Holbert [:dholbert]]

Attachment: dholbert's screencast using explicit "clear recent history"

Comment 22

[Daniel Holbert [:dholbert]]

Comment 21 is a screencast of my STR in comment 20.
Notes:

• At t=22s, I do step 4 from my comment 20 STR -- a "full" refresh (holding Shift, though you can't tell from the screencast), and the image disappears from my shortcut tile.
• At t=26s, I do step 5 from my comment 20 STR -- open a new tab -- and the image is back somehow.
• At t=29s, I do step 6 from my comment 20 STR -- open a bunch more new tabs -- and the image is gone in all of them..