Ooh, that tethering piece is interesting… What does ip link show give you?
The tethering interface is probably named something like usb0 or enp*usb*; specifically, we’re interested in the MTU value because mobile tethering often sets MTU to 1500 but the actual path MTU is lower, which can make large TLS handshakes fragment and fail silently.
ip link show returns
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT group default qlen 1000
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
2: enp7s0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc fq_codel state DOWN mode DEFAULT group default qlen 1000
link/ether 9c:6b:00:87:7b:8a brd ff:ff:ff:ff:ff:ff
altname enx9c6b00877b8a
3: enp9s0f3u2: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UNKNOWN mode DEFAULT group default qlen 1000
link/ether 92:93:f3:88:78:1e brd ff:ff:ff:ff:ff:ff
altname enx9293f388781e
There it is! enp9s0f3u2 looks like the tether and its MTU is at 1500. Try this:
sudo ip link set enp9s0f3u2 mtu 1400
steam
If Steam launches, great and we can make that change permanent; if not, we’ll need to step down the MTU further.
it did not launch. should I try 1000? by the way how did you point out the tethering serial?
Yeah. you are right. I just checked the device and that is the one. thanks
I forgot to ask. should I do any type of clearing before trying to launch steam?
1000 is too low because Google tells me the IPv6 spec minimum is 1280. 
The name enp9s0f3u2 is fairly readable in linux’s network interface naming conventions; e.g., en is ethernet, p9s0 PCI bus 9, slot 0 (so, the physical USB controller on the motherboard), f3 is function 3 of that controller, and u2 stands for USB port 2. Since your other interface, enp7s0, had no carrier and no cable plugged in, enp9s0f3u2 had to be the active connection.
Let’s try:
sudo ip link set enp9s0f3u2 mtu 1280
steam
I will try that. I’m really sorry. Power went out again. So, you can focus on your important work. I’ll let you know when I run the command and what it returns.
Not at all… The power going out is a lot more inconvenient for you than me.
But I have a feeling we are getting close to the main source of problem. Can’t thank you enough for your time and effort 
.
sadly it didn’t work either.
I’m going to remove steam and try reinstalling. we have spent enough time trying to find the issue.
The reinstall should have fixed it, but a complete tear-down and rebuild might work.
Best of luck!
I’m kind of embarrassed. Power went out again while doing that. Maybe today is not the day. Anyway I think I’ll try lutris. I’m a very casual gamer who just plays games for 1 hour in a day or two. Today I was just trying to wind off some stress but instead got a lot more
. I’m going to simply sleep today and call it a day. Thank you very much for your help. Good night
.
You’re very welcome… I’ve come to this forum enough times tearing my hair out and getting the help I needed that I just want to give back a bit.
Ah! So, everyone is a survivor here.
Just to let you know, I removed steam fully and migrated to lutris and it’s working fine(and I just play one game anyway). Still it’s a mystery how steam got into that position. I think the steam problem is much deeper than it appears. Maybe steam and modern fedora has internal collision that is still not fully visible.
Steam works fine of uptodate fedora 44.
oh! nice. But I can’t understand how mine got corrupted just by clearing download cache which even a full wipe out and reinstall couldn’t fix. But it’s alright. I wasn’t using steam for it’s library rather just for compatibility.
Maybe you only cleated out part the steam cache/config and left a broken something behind.
One way to find out is to create a new user and login as them then test the software that has broken. If it works you know it’s an issue with files in your original user’s account.