Clean RAM after some days of PC usage

I have 8GB RAM, and use my PC (Debian 10, KDE plasma 5.14.5) "normally" but with many programs running in parallel: - Firefox (≈ 250 Tabs) - Chromium (10 Tabs) - Thunderbird - 10x Okular - 2x Pycharm - 5x Konsole - Dolphin - Kile - Element, Telegram, Wikidpad, ... After a fresh restart RAM consumption of my system is at about 4GB. Everything runs smoothly and fast. After several days (with suspend over night) RAM consumption is at about 7.5GB and it takes e.g. 10s to switch from Firefox to Dolphin. I already tried ([source](https://unix.stackexchange.com/questions/87908/how-do-you-empty-the-buffers-and-cache-on-a-linux-system))

# echo 1 > /proc/sys/vm/drop_caches
# echo 2 > /proc/sys/vm/drop_caches
# echo 3 > /proc/sys/vm/drop_caches

but it had no significant effect. This is the output of free -m:

total        used        free      shared  buff/cache   available
Mem:           7754        5163         950         588        1641        1708
Swap:         19071         704       18367

swapon -s gives:

Filename                                Type            Size    Used    Priority
/dev/dm-1                               partition       19529724        720896  -2

**Question**: How can I "clean" the RAM to get back the situation after restart (+ automatic program launches) but without doing an actual restart? Disclaimer: This question got some comments on [askubuntu.com/...](https://askubuntu.com/questions/1321011/clean-ram-after-some-days-of-pc-usage) but was regarded as offtopic for that site.