Be careful with old versions!
These versions are displayed for reference and testing purposes. You should always use the latest version of an add-on.
It also has a new user interface for a feature that's existed for a long time. You can use it to restrict the number of tiles (from your browsing history) that appear from any site. For example, Facebook may appear 5 times in your most-visited sites, but you only want one tile on your new tab page.
There's also a few bug fixes but none worth detailing here.
This version also contains updates to the Latvian translation, and a new Hungarian translation. Thanks to the translators!
Additionally the unused multiple backgrounds feature has been removed, as it is still buggy and I have no time to maintain it.
This might be the last version of New Tab Tools. I'm getting really fed up with jumping through Mozilla's hoops when there's so little in it for me.
Upcoming changes to Firefox's thumbnail-creation code have been producing low-quality thumbnails. New Tab Tools now tweaks some relevant preferences to improve the quality. It is possible to turn this off, by setting
extensions.newtabtools.thumbs.prefs.delayto -1. Values of 0 or above are the number of seconds after the new tab page loads that the thumbnail size is calculated.
The first New Tab Tools data collection experiment is contained in this version (English language users only). It will run until the end of January and collect the values of some NTT preferences. Please help by opting in to data collection (tick the checkbox in the preferences panel). No data is collected if you do not opt in.
See this link for version 56's release notes: https://addons.mozilla.org/firefox/addon/new-tab-tools/versions/56
Or to see the same updates without the massive code-style changes:
Also included for the first time is the "multiple background images" feature. It may be buggy so there is currently no UI for it and it is off by default. If you would like to test the feature, see this GitHub issue. Please report any problems you find.
This version has updates for the Latvian, Brazilian Portuguese, Greek, and Chinese (Simplified) translations. I've also moved the context menu items (introduced in v49) down the menu to a more-sensible place.
Changes in Firefox Nightly have broken New Tab Tools recently and will do again. There's one fix included here but bigger changes are going to be required soon.
There are other minor changes, and updates to the French and Brazilian Portuguese translations.