Sorry, if this is the wrong category; would someone kindly correct this if so. Some websites, and I do not know what is different about them, will not display their text in certain areas under XFCE 4.12, but will display correctly in LXDE. Using Debian 9 stretch. Steps to reproduce: 1. Install LXDE. 2. In XFCE 4.12, use Firefox or Chrome browser to open https://franciscanhealth.org/find-a-doctor. 3. Observe that there are places of obvious missing text. Changing appearance, theme, or compositing on/off make no difference. 4. Log out. 5. Change from XFCE to LXDE. 6. Repeat step 2 and observe correctly displayed page.
I think you need to add a screenshot for me to better understand the issue. Also, please test with Xfce 4.14pre1 or pre2. It should be available in several distributions or also via xfce-test https://github.com/schuellerf/xfce-test (The 4.12 release will very likely not receive such fixes anymore.)
I don't think this has anything to do with Xfce panel, here I even launch firefox from the keyboard shortcut, and have no idea if it has something to do with Xfce as I have only this DE installed right now. But I noticed in a mozilla page that an alert banner is blank too. https://postimg.cc/Mn1zZPRg
What Gtk+ theme are you using? That could be at fault here. (It doesn't look like plain Greybird with the blue menu bar but like a mix with Bluebird)
I'm using Bluebird. Here the page the OP mentioned also doesn't display properly. But I don't know if the gtk3 theme has anything to do as it looks the same with other themes (actually I don't even know if Xfce has anything to do with it). But I think Firefox has issues with gtk3 so maybe when the OP uses it with LXDE then maybe it's using gtk2? I always thought the web content wasn't affected by the DE environment.
Created attachment 8724 Good display screenshot as requested using LXDE
Created attachment 8725 screenshot of bad display as requested
Please find attached both good and bad screenshots. I must apologize for my lack of expertise and limited resources, but I do not have the bandwidth or a reliable internet connection to download a whole new distro. And, Docker will not let me create an account for some reason. Thus, I am not able to try a later version of XFCE. However, I have a little more information: First, as noted above, this is not limited to Firefox, but also affects the Google Chrome browser. I also reproduced the problem on both Firefox Quantum and Firefox ESR. Also, I reproduced the problem on another machine, showing that the problem is independent of video card, video driver, or theme, all of which are different. Finally, Mate also gives a correct display, showing that the difference is not unique to LXDE. Hope this helps.
This is a font issue, the web pages set its own custom fonts which cannot show for some reason. I can also reproduce the same issue in GNOME as well. Could be a locale/encoding issue as well. But in Firefox, if you unselect “Allow pages to choose their own fonts, instead of your selections above” in Firefox preferences, the text will show up.
Oliver Fourdan: Interesting find and observation. I can confirm this. (For what it is worth, Firefox settings do persist across XFCE/LXDE changes.) But fonts are stored in local directories, not in directories specific to LXDE or XFCE, are they not? Or am I wrong about this. Many thanks to all.
Same with google-chrome, running “google-chrome --disable-remote-fonts” also fixes the issue. I have no idea why it would behave differently in lxde.
Not a bug in the panel.