When starting kmail or kmail in kontact after booting up, it randomly crashes. The UI appears, a message box says: (translating from German)  "A severe error occured in the e-mail-program. The program is terminated." Clicking on OK closes kmail. (It seems that new mails etc. are downloaded in the background.)

Starting 4-5 times seems to guarantee to get kmail up running. My impression (and from the result listed below) is that it's struggling to connect to Akonadi.

Reproducible: Sometimes

Steps to Reproduce:
1. start kmail or kontact

Actual Results:  
Kmail/Kontact crashes.

The output to a terminal when the crash happens:

Pass a valid window to KWallet::Wallet::openWallet().
 void AdblockManager::reloadConfig() false    AdBlock::AdblockManager(0x1f4fb40)
this does not work on a KActionCollection containing actions!
org.kde.akonadi.ETM: GEN true false false
org.kde.akonadi.ETM: collection: QVector()
org.kde.akonadi.ETM: 
log_akonadicore: Invalid command, the world is going to end!
QIODevice::read (QLocalSocket): device not open
org.kde.akonadi.ETM: Subtree:  141 QSet(387, 386, 389, 388, 391, 390, 393, 392, 395, 394, 397, 396, 399, 398, 497, 496, 499, 498, 501, 500, 503, 502, 505, 504, 507, 506, 509, 508, 511, 510, 481, 480, 483, 482, 485, 484, 487, 486, 489, 488, 491, 490, 493, 492, 495, 494, 465, 464, 467, 466, 469, 468, 471, 470, 473, 472, 475, 474, 477, 476, 479, 478, 449, 448, 451, 450, 453, 452, 455, 454, 457, 456, 459, 458, 461, 460, 463, 462, 561, 560, 563, 562, 565, 564, 567, 566, 569, 568, 571, 570, 573, 572, 575, 574, 545, 544, 547, 546, 549, 548, 551, 550, 553, 552, 555, 554, 557, 556, 559, 558, 529, 528, 531, 530, 533, 532, 535, 534, 537, 536, 539, 538, 541, 540, 543, 542, 513, 512, 515, 514, 517, 516, 519, 518, 521, 520, 523, 522, 525, 524, 527, 526, 577, 576, 583, 585, 584, 587, 586, 588, 177, 179, 178, 181, 180, 183, 182, 185, 184, 187, 186, 189, 188, 191, 190, 145, 147, 146, 149, 148, 151, 150, 153, 152, 155, 154, 157, 156, 158, 141, 241, 240, 243, 242, 245, 244, 247, 246, 249, 248, 251, 250, 253, 252, 255, 254, 225, 224, 227, 226, 229, 228, 231, 230, 233, 232, 235, 234, 237, 236, 239, 238, 209, 208, 211, 210, 213, 212, 215, 214, 217, 216, 219, 218, 221, 220, 223, 222, 193, 192, 195, 194, 197, 196, 199, 198, 201, 200, 203, 202, 205, 204, 207, 206, 305, 304, 307, 306, 309, 308, 311, 310, 313, 312, 315, 314, 317, 316, 319, 318, 289, 288, 291, 290, 293, 292, 295, 294, 297, 296, 299, 298, 301, 300, 303, 302, 273, 272, 275, 274, 277, 276, 279, 278, 281, 280, 283, 282, 285, 284, 287, 286, 257, 256, 259, 258, 261, 260, 263, 262, 265, 264, 267, 266, 269, 268, 271, 270, 369, 368, 371, 370, 373, 372, 375, 374, 377, 376, 379, 378, 381, 380, 383, 382, 353, 352, 355, 354, 357, 356, 359, 358, 361, 360, 363, 362, 365, 364, 367, 366, 337, 336, 339, 338, 341, 340, 343, 342, 345, 344, 347, 346, 349, 348, 351, 350, 321, 320, 323, 322, 325, 324, 327, 326, 329, 328, 331, 330, 333, 332, 335, 334, 433, 432, 435, 434, 437, 436, 439, 438, 441, 440, 443, 442, 445, 444, 447, 446, 417, 416, 419, 418, 421, 420, 423, 422, 425, 424, 427, 426, 429, 428, 431, 430, 401, 400, 403, 402, 405, 404, 407, 406, 409, 408, 411, 410, 413, 412, 415, 414, 385, 384)
org.kde.akonadi.ETM: Fetch job took  148 msec
org.kde.akonadi.ETM: was collection fetch job: collections: 422
org.kde.akonadi.ETM: first fetched collection: "Lokale Ordner"
log_akonadicore: ""
log_akonadicore: Failed SpecialCollectionsRequestJob::slotResult "Verbindung zum Akonadi-Dienst kann nicht hergestellt werden."
log_mailcommon: "Im E-Mail-Programm ist ein schwerwiegender Fehler aufgetreten. Das Programm wird beendet."
org.kde.akonadi.ETM: collection: QVector()
org.kde.akonadi.ETM: Fetch job took  258 msec
org.kde.akonadi.ETM: was collection fetch job: collections: 8
org.kde.akonadi.ETM: first fetched collection: "Search"
org.kde.akonadi.ETM: Fetch job took  46 msec
org.kde.akonadi.ETM: was collection fetch job: collections: 0
org.kde.akonadi.ETM: collection: "Admin - done"
org.kde.akonadi.ETM: collection: "Admin - todo"
org.kde.akonadi.ETM: collection: "Family"
org.kde.akonadi.ETM: collection: "Geschäftliches"
org.kde.akonadi.ETM: collection: "My Research Projects - done"
org.kde.akonadi.ETM: collection: "My Research Projects - todo"
org.kde.akonadi.ETM: collection: "Other Academic, Travel - done"
org.kde.akonadi.ETM: collection: "Other Academic, Travel - todo"
org.kde.akonadi.ETM: collection: "Private"
org.kde.akonadi.ETM: collection: "Teaching, Mentoring, PhDs - done"
org.kde.akonadi.ETM: collection: "Teaching, Mentoring, PhDs - todo"
org.kde.akonadi.ETM: collection: "tosort-done"
org.kde.akonadi.ETM: collection: "signed-off"
org.kde.akonadi.ETM: collection: "excuses"
org.kde.akonadi.ETM: collection: "other projects"
org.kde.akonadi.ETM: Fetch job took  121 msec
org.kde.akonadi.ETM: was item fetch job: items: 393
org.kde.akonadi.ETM: Fetch job took  165 msec
org.kde.akonadi.ETM: was item fetch job: items: 80
org.kde.akonadi.ETM: Fetch job took  202 msec
org.kde.akonadi.ETM: was item fetch job: items: 37
org.kde.akonadi.ETM: Fetch job took  237 msec
org.kde.akonadi.ETM: was item fetch job: items: 34
org.kde.akonadi.ETM: Fetch job took  276 msec
org.kde.akonadi.ETM: was item fetch job: items: 62
org.kde.akonadi.ETM: Fetch job took  306 msec
org.kde.akonadi.ETM: was item fetch job: items: 6
org.kde.akonadi.ETM: Fetch job took  341 msec
org.kde.akonadi.ETM: was item fetch job: items: 94
org.kde.akonadi.ETM: Fetch job took  371 msec
org.kde.akonadi.ETM: was item fetch job: items: 0
org.kde.akonadi.ETM: Fetch job took  404 msec
org.kde.akonadi.ETM: was item fetch job: items: 53
org.kde.akonadi.ETM: Fetch job took  444 msec
org.kde.akonadi.ETM: was item fetch job: items: 307
org.kde.akonadi.ETM: Fetch job took  474 msec
org.kde.akonadi.ETM: was item fetch job: items: 14
org.kde.akonadi.ETM: Fetch job took  505 msec
org.kde.akonadi.ETM: was item fetch job: items: 14
org.kde.akonadi.ETM: Fetch job took  549 msec
org.kde.akonadi.ETM: was item fetch job: items: 13
org.kde.akonadi.ETM: Fetch job took  600 msec
org.kde.akonadi.ETM: was item fetch job: items: 32
org.kde.akonadi.ETM: Fetch job took  633 msec
org.kde.akonadi.ETM: was item fetch job: items: 1
*** KMail got signal 11 (Exiting)
Speicherzugriffsfehler (Speicherabzug geschrieben)


Expected Results:  
kmail should start up.

I've the latest KDE5/Kmail packages installed from opensuse Tumbleweed.