"Without login" and "secure" don't really go together in the same context ;)
You can create a guest account. Access is done via a special link, no login.
You can also configure FileRun with an external location for the thumbnail cache. See $config['path']['thumbnail_cache'] on this page.
P.S. PHP configurations or file permissions are not something FileRun would or could cache. If you are running on a shared hosting service: some providers implement their own aggressive caching on the filesystem for optimizing their hardware resources.
This will be added with the next update.
To customize a folder's icon, one would set a CSS class name for the folder's path, inside "customizables/config.php", like this:
$config['app']['ui']['folder_icon_css_class']['/the/folder/s/path'] = 'themeColorMain fa-exclamation-triangle';
Replace "/the/folder/s/path" with the actual folder's absolute path.
The CSS class name "themeColorMain" is used to keep the icon's color consistent with the theme's color. The "fa-exclamation-triangle" is a Font Awesome icon class name (note that not all Font Awesome icons are defined by default in FileRun, so check the file "css/font-awesome/css/font-awesome.min.css" for availability - do not edit this file though).
Any custom CSS definition can be set through enabling the loading of a custom CSS file (see http://docs.filerun.com/custom_css).
Then you won't want to allow uploads either, because if a file is overwritten by another file and its name is changed, then wouldn't one consider that the original file was deleted?
Then if you disable uploads, why allow users to move files around.
Given that you can disable users permissions to make changes, at this time we do not plan to add such option. I will leave the thread open for voting though.
I have renamed the topic to make more accurate to the problem description.
FileRun does not use ImageMagick or does any processing to small image files. The thumbnails are the files themselves.
If you don't get thumbnails for files that FileRun is actually using ImageMagick with, it means one of the two: 1) ImageMagick doesn't work, 2) PHP doesn't have write permissions to the browsed folders (which it needs for writing the thumbnail cache)
Use the Nextcloud mobile app instead: https://play.google.com/store/apps/details?id=com.nextcloud.client&rdid=com.nextcloud.client
For anything else other than keeping files offline or syncing, you can access the FileRun instlalation using a regular mobile browser.
The reason why we cannot implement this is the fact that it is not an open API. Each and every one of you would have to manually make a request to Microsoft to join a partner program in order to get access to the API: https://developer.microsoft.com/en-us/office/cloud-storage-partner-program#Signup The sign up is not automatic.
After that: "Microsoft will validate your WOPI implementation as well as your UI integration. Depending on what issues are uncovered during validation, this may take some time. You should estimate a two-week turnaround time assuming there are no major issues uncovered. However, we recommend allowing at least a month unless your integration is very simple."
And what are you using instead?
Currently there is no detailed view.
See the folder "wl/css/" for styling the web links pages.
When creating a web link, right next to the field that displays the link's URL, you have a toggle option that reads by default "Grid view". Click on it to change the display mode and the URL changes accordingly.
There are currently a couple of places that do not take the theme into account. The web links being one of them. This will be improved in the future.
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