[SOLVED] Flash in fullscreen breaks plasmshell

[pemartins]

When I run flash videos in Firefox, in example::

https://student.testmasters.com/portal/online/Test.aspx

if I put the player in full screen it breaks plasmashell and kwin also, I believe. I have to run:

killall plasmashell && kwin && plasmashell &

and close the Firefox flash tab in order to get things working again.

Does anyone else have this issue?

System:    Host: pemartins-X55U Kernel: 4.15.0-38-generic x86_64 bits: 64 Desktop: KDE Plasma 5.14.2
        Distro: KDE neon User Edition 5.14
Machine:   Device: laptop System: ASUSTeK product: X55U v: 1.0 serial: N/A
        Mobo: ASUSTeK model: X55U v: 1.0 serial: N/A
        UEFI: American Megatrends v: X55U.423 date: 08/06/2013
CPU:       Dual core AMD E2-1800 APU with Radeon HD Graphics (-MCP-) cache: 512 KB
        clock speeds: max: 1700 MHz 1: 871 MHz 2: 872 MHz
Graphics:  Card: Advanced Micro Devices [AMD/ATI] Wrestler [Radeon HD 7340]
        Display Server: x11 (X.Org 1.19.6 ) drivers: ati,radeon (unloaded: modesetting,fbdev,vesa)
        Resolution: 1366x768@60.01hz
        OpenGL: renderer: AMD PALM (DRM 2.50.0 / 4.15.0-38-generic, LLVM 6.0.0) version: 3.3 Mesa 18.0.5
Audio:     Card-1 Advanced Micro Devices [AMD] FCH Azalia Controller driver: snd_hda_intel
        Card-2 Advanced Micro Devices [AMD/ATI] Wrestler HDMI Audio driver: snd_hda_intel
        Sound: Advanced Linux Sound Architecture v: k4.15.0-38-generic
Network:   Card-1: Ralink RT5390 Wireless 802.11n 1T/1R PCIe driver: rt2800pci
        IF: wlp1s0 state: up mac: <filter>
        Card-2: Qualcomm Atheros AR8161 Gigabit Ethernet driver: alx
        IF: enp2s0 state: down mac: <filter>
Drives:    HDD Total Size: 500.1GB (8.5% used)
        ID-1: /dev/sda model: ST500LM012_HN size: 500.1GB
Partition: ID-1: / size: 97G used: 37G (40%) fs: ext4 dev: /dev/sda5
        ID-2: swap-1 size: 3.85GB used: 0.00GB (0%) fs: swap dev: /dev/sda6
RAID:      No RAID devices: /proc/mdstat, md_mod kernel module present
Sensors:   System Temperatures: cpu: 59.0C mobo: N/A gpu: 59.0
        Fan Speeds (in rpm): cpu: 3100
Info:      Processes: 164 Uptime: 35 min Memory: 1310.0/3528.9MB Client: Shell (xterm) inxi: 2.3.56

edit: I'm using the latest Firefox version Firefox Quantum 63.0 (64-bit).

[pemartins]

I had to reinstall the system and it did not happen again. It was an isolated incident.
Marking this one as solved.