Android 6 w/ Chrome: cannot scroll thru folders in Settings -> Folders

[faginbagin]

I cannot manage folder subscriptions on my Android tablet because I cannot scroll thru the list of folders when I choose Settings -> Folders. The middle Folders pane acts as if there is no scroll bar, even though only about 1/4 of my folders are displayed.

The tablet is a Samsung Galaxy Tab S, Model SM-T800, running Android 6.0.1 with Google Chrome 69.0.3497.100

Roundcube is installed on Debian Stretch with php 7.0.30, apache 2.4.25, mariadb 10.1.26. I had originally installed roundcube 1.2.3 from the debian stretch repo, but when I hit this issue, I first upgraded to 1.3.6 by downloading and installing the .deb packages from the buster/testing repo. When that didn't fix it, I downloaded and installed 1.3.7 from here:
https://github.com/roundcube/roundcubemail/releases/download/1.3.7/roundcubemail-1.3.7-complete.tar.gz
Still no joy. The only plugins are filesystem_attachments 1.0 and jqueryui 1.12.0.

I can scroll through the folders using these OS, browser combinations:
Ubuntu 18.04.1, Firefox Quantum 62.0 (64-bit)
Windows 10, Google Chrome 69.0.3497.100 (Official Build) (64-bit)
Windows 10, Microsoft Edge 42.17134.1.0

And I can scroll though the subscribed folders when I read mail on all OS, browser combos, including the android tablet. But that doesn't help me manage which folders I subscribe to.

I'm attaching two screenshots:
roundcube-android-chrome-50.jpg - shows the problem page on android & chrome
roundcube-win10-chrome.png - shows there are many more folders I can get to on windows 10 & chrome

Roundcube is on my personal web server. I've got full access and I'm also a software developer, although I've only tinkered with php. I can certainly apply and test patches, submit pull requests on github, and maybe do some coding. Please let me know how I can help improve roundcube.

[JohnDoh]

The Larry skin (or the classic skin) is not designed for use on mobiles/tablets. Roundcube 1.4 (currently in Beta) has the new responsive Elastic skin which supports mobiles, tables and desktops.

[faginbagin]

This is a 10.5 inch tablet. I can't think of a web site designed for desktops that doesn't work on it, except for roundcube. Plus, as I mentioned, I CAN scroll through the list of folders in the left pane when reading email. I can also scroll through the right hand pane containing the list of messages. Why not the middle pane that contains the folders in Settings->Folders? My guess something different is being done when that middle pane is being created vs all other panes in roundcube.

I intend to do more tinkering to get roundcube working on a phone, but I don't see why a desktop interface shouldn't be fully functional on a large tablet. Can anyone give me a starting point where that middle pane is created? Maybe I can figure it out, even with my limited php experience.

[alec]

From what I remember the drag'n'drop handling code does not work properly with touch events. That's why drag'n'drop is disabled on touch devices in the Elastic skin. Javascript experience will be needed if you tend to remove that limitation.

[faginbagin]

Thanks for the heads up re: drag & drop. I have also tinkered with javascript, although I've tinkered with php more recently. Maybe I'll put this on hold while I work on other projects, in anticipation of 1.4 coming out of beta.