$ doomseeker
[20:44:27] Starting Doomseeker. Hello World! :)
[20:44:27] Setting up data directories.
[20:44:27] Attempting to load plugins from directory: /home/wub/.doomseeker/engines
[20:44:27] Attempting to load plugins from directory: /usr/bin/engines
[20:44:27] Attempting to load plugins from directory: engines
[20:44:27] Attempting to load plugins from directory: /usr/share/doomseeker/engines
[20:44:27] Loaded plugin: "Zandronum"!
[20:44:27] Listening to Zandronum's LAN servers broadcasts on port 15101.
[20:44:27] Initializing configuration file.
[20:44:27] Setting INI file: /home/wub/.doomseeker/doomseeker.ini
[20:44:27] Loading translations definitions
[20:44:27] Loading translation "en_US".
[20:44:27] Translation 'qt_en_US' not found.
[20:44:27] Translation 'en_US' not found.
[20:44:27] Failed to load translation.
[20:44:27] Initializing IP2C database.
[20:44:27] Initializing passwords configuration file.
[20:44:27] Initializing configuration for plugins.
[20:44:27] Initializing IRC configuration file.
[20:44:27] Setting IRC INI file: /home/wub/.doomseeker/doomseeker-irc.ini
[20:44:27] Starting refreshing thread.
[20:44:27] Preparing GUI.
[20:44:27] Please wait. IP2C database is being read. This may take some time.
[20:44:27] Parsing IP2C database: :/IpToCountry.dat
[20:44:27] IP2C database read in 63 ms. Entries read: 119365
[20:44:27] Init finished.
================================
[20:44:27] IP2C parsing thread has finished.
[20:44:27] IP2C parsing finished.

Quote
Zandronum plugin is definitely loaded, reports servers on the list, but the GUI tells there are none even with cursor focus on the window.

[01:34:50] Parsing IP2C database: /home/doomseeker/.local/share/data/doomseeker/
IpToCountry.dat
Qt has caught an exception thrown from an event handler. Throwing
exceptions from an event handler is not supported in Qt. You must
reimplement QApplication::notify() and catch all exceptions there.

terminating with uncaught exception of type std::bad_alloc: std::bad_alloc
Abort trap (core dumped)

(gdb) bt       
#0  thrkill () at -:3
#1  0x000002c607f9655e in _libc_abort () at /usr/src/lib/libc/stdlib/abort.c:51
Die: DW_TAG_unspecified_type (abbrev = 4, offset = 251222)
        has children: FALSE
        attributes:
                DW_AT_name (DW_FORM_strp) string: "decltype(nullptr)"
Dwarf Error: Cannot find type of die [in module /usr/lib/libc++abi.so.0.1]

Quote from WubTheCaptain
Qt has caught an exception thrown from an event handler. Throwing
exceptions from an event handler is not supported in Qt. You must
reimplement QApplication::notify() and catch all exceptions there.

[02:05:13] Setting IRC INI file: /home/doomseeker/.doomseeker/doomseeker-irc.ini
[02:05:13] Starting refreshing thread.
[02:05:13] Preparing GUI.
[02:05:13] Please wait. IP2C database is being read. This may take some time.
[02:05:13] Parsing IP2C database: /home/doomseeker/.doomseeker/IpToCountry.dat
[02:05:13] Init finished.
================================
[02:05:13] Total refresh process initialized!
[02:05:14] IP2C database read in 340 ms. Entries read: 175445
[02:05:14] IP2C parsing thread has finished.
[02:05:14] IP2C parsing finished.
LookupHostConsumerThread: 0x10c6777b8c40
terminating with uncaught exception of type std::bad_alloc: std::bad_alloc
Abort trap (core dumped)

Quote from WubTheCaptain
Now my Doomseeker 1.1 doesn't list servers due to this fault or something else, heh. (Recreating the .doomseeker directory will probably fix this.)

1. 4 GB RAM in a virtual machine is not enough to run X with fvwm and Doomseeker (untrue); or
   
2. /etc/login.conf memory limits on users limit the maximum available memory to programs.

Quote from Zalewa
Let's return to this when we go forth with 0003541 and see if it still happens.

Quote from 1.3, no ~/.local/share/IpToCountry.dat

[12:41:40] Preparing GUI.
[12:41:40] Checking if IP2C database at '/usr/share/doomseeker/IpToCountry.dat' needs updating.
[12:41:40] Please wait. IP2C database is being read. This may take some time.
[12:41:40] Parsing IP2C database: /usr/share/doomseeker/IpToCountry.dat
[12:41:40] Init finished.
================================
[12:41:40] IP2C database read in 99 ms. Entries read: 196041
[12:41:40] Total refresh initialized!
[12:41:40] IP2C parsing thread has finished.
[12:41:40] IP2C parsing finished.
[12:41:41] Comparing IP2C hashes: local = aeca013c6eb838531099b9727f2187a0, remote = aeca013c6eb838531099b9727f2187a0

[12:41:41] IP2C update not needed.
[12:41:44] Finished refreshing. Servers on the list: 512 (+2 custom, +0 LAN). Players: 51.

Quote from 1.3, manually updated to acquire ~/.local/share/IpToCountry.dat

[12:43:42] Preparing GUI.
[12:43:42] Checking if IP2C database at '/home/wub/.local/share/doomseeker/IpToCountry.dat' needs updating.

[12:43:42] Please wait. IP2C database is being read. This may take some time.
[12:43:42] Parsing IP2C database: /home/wub/.local/share/doomseeker/IpToCountry.dat
[12:43:42] Init finished.
================================
[12:43:42] IP2C database read in 100 ms. Entries read: 196041
[12:43:42] Total refresh initialized!
[12:43:42] IP2C parsing thread has finished.
[12:43:42] IP2C parsing finished.
[12:43:42] Comparing IP2C hashes: local = aeca013c6eb838531099b9727f2187a0, remote = aeca013c6eb838531099b9727f2187a0

[12:43:42] IP2C update not needed.
[12:43:45] Finished refreshing. Servers on the list: 513 (+2 custom, +0 LAN). Players: 53.

Quote from 1.3 + patch, no ~/.local/share/IpToCountry.dat, with IP2C autoupdate

[12:44:53] Preparing GUI.
[12:44:53] Starting IP2C update.
[12:44:53] Init finished.
================================
[12:44:53] Total refresh initialized!
[12:44:55] IP2C database finished downloading.
[12:44:55] Please wait. IP2C database is being read. This may take some time.
[12:44:55] Parsing IP2C database: /home/wub/.local/share/doomseeker/IpToCountry.dat
[12:44:55] IP2C database read in 220 ms. Entries read: 196041
[12:44:55] IP2C parsing thread has finished.
[12:44:55] IP2C parsing finished.
[12:44:57] Finished refreshing. Servers on the list: 665 (+2 custom, +0 LAN). Players: 341.

Quote from 1.3 + patch, no ~/.local/share/IpToCountry.dat, IP2C autoupdate disabled

[13:34:27] Initializing IP2C database.
[13:34:27] Initializing passwords configuration file.
[13:34:27] Initializing configuration for plugins.
[13:34:27] Initializing IRC configuration file.
[13:34:27] Setting IRC INI file: /home/wub/.config/doomseeker/doomseeker-irc.ini
[13:34:27] Starting refreshing thread.
[13:34:27] Preparing GUI.
[13:34:27] Did not find any IP2C database. IP2C functionality will be disabled.
[13:34:27] You may install an IP2C database from the "File" menu.
[13:34:27] Init finished.
================================
[13:34:27] Total refresh initialized!
[13:34:31] Finished refreshing. Servers on the list: 652 (+2 custom, +0 LAN). Players: 249

Quote from 1.3 + patch, ~/.local/share/IpToCountry.dat exists

[12:46:57] Preparing GUI.
[12:46:57] Checking if IP2C database at '/home/wub/.local/share/doomseeker/IpToCountry.dat' needs updating.

[12:46:57] Please wait. IP2C database is being read. This may take some time.
[12:46:57] Parsing IP2C database: /home/wub/.local/share/doomseeker/IpToCountry.dat
[12:46:57] Init finished.
================================
[12:46:57] Total refresh initialized!
[12:46:58] IP2C database read in 228 ms. Entries read: 196041
[12:46:58] IP2C parsing thread has finished.
[12:46:58] IP2C parsing finished.
[12:46:58] Comparing IP2C hashes: local = aeca013c6eb838531099b9727f2187a0, remote = aeca013c6eb838531099b9727f2187a0

[12:46:58] IP2C update not needed.
[12:47:01] Finished refreshing. Servers on the list: 666 (+2 custom, +0 LAN). Players: 339.

• 2020-01-19-125651_maim.png is from 1.3+patch
  
• 2020-01-19-125725_maim.png is from 1.3

1. Have an up-to-date /usr/share/doomseeker/IpToCountry.dat (as in official release; adapt to CMAKE_INSTALL_PREFIX with source builds, which may be /usr/local/share/doomseeker/IpToCountry.dat)
   
2. Install all game plugins (sudo apt install doomseeker-*)
   
3. Set (or assume) IP2CAutoUpdate=0 in doomseeker.ini (~/.config/doomseeker/doomseeker.ini)
   
4. Start Doomseeker.
   
5. Enable querying all five servers. ("Query" top navigation menu. I used to usually query Zandronum only.)
   
6. Enable IP2C auto update: Options → Configure (F5) → Auto Updates → IP2C auto update
   
7. Enable refresher on startup: Options → Configure (F5) → Query → Refresh servers on startup
   
8. Click "OK" to save the configuration changes.
   
9. Close Doomseeker.
   
10. Build an outdated IpToCountry.dat blob from source (I used 28eeb49) and copy the outdated IpToCountry.dat to local user directory (~/.local/share/doomseeker/IpToCountry.dat)
    
11. Start Doomseeker and hope to crash.