Telegram crashes at startup (cannot sync properly)

By the way I am not able to upload the crash report. I have no idea how this could work, since ubuntu-bug does not allow me any option to attach it to here...

Part of the (hopefully) relevant stacktrace:

== Stacktrace =================================
#0 0xb5ad39a6 in ?? () from /lib/arm-linux-gnueabihf/libc.so.6
No symbol table info available.
#1 0xb5ae162e in raise () from /lib/arm-linux-gnueabihf/libc.so.6
No symbol table info available.
#2 0xb5ae2332 in abort () from /lib/arm-linux-gnueabihf/libc.so.6
No symbol table info available.
#3 0xb5d85d34 in QMessageLogger::fatal(char const*, ...) const () from /usr/lib/arm-linux-gnueabihf/libQt5Core.so.5
No symbol table info available.
#4 0xb5d82c26 in qt_assert(char const*, char const*, int) () from /usr/lib/arm-linux-gnueabihf/libQt5Core.so.5
No symbol table info available.
#5 0xb3a1b9c0 in Decrypter::fetchDecryptedMessageAction() () from /opt/click.ubuntu.com/.click/users/@all/com.ubuntu.telegram/lib/arm-linux-gnueabihf/libqtelegram-ae.so.1
No symbol table info available.
#6 0xb3a1bc1c in Decrypter::fetchDecryptedMessage() () from /opt/click.ubuntu.com/.click/users/@all/com.ubuntu.telegram/lib/arm-linux-gnueabihf/libqtelegram-ae.so.1
No symbol table info available.
#7 0xb3a1ca80 in Decrypter::decryptEncryptedData(long long, QByteArray const&) () from /opt/click.ubuntu.com/.click/users/@all/com.ubuntu.telegram/lib/arm-linux-gnueabihf/libqtelegram-ae.so.1
No symbol table info available.
#8 0xb3a5425a in Telegram::toSecretChatMessage(EncryptedMessage const&) () from /opt/click.ubuntu.com/.click/users/@all/com.ubuntu.telegram/lib/arm-linux-gnuea:
No symbol table info available.
#9 0xb3a5864c in Telegram::processDifferences(long long, QList<Message> const&, QList<EncryptedMessage> const&, QList<Update> const&, QList<Chat> const&, QList<User> const&, UpdatesState const&, bool) () from /opt/click.ubuntu.com/.click/users/@all/com.ubuntu.telegram/lib/arm-linux-gnueabihf/libqtelegram-ae.so.1
No symbol table info available.
#10 0xb3a58800 in Telegram::onUpdatesDifference(long long, QList<Message> const&, QList<EncryptedMessage> const&, QList<Update> const&, QList<Chat> const&, QList<User> const&, UpdatesState const&) () from /opt/click.ubuntu.com/.click/users/@all/com.ubuntu.telegram/lib/arm-linux-gnueabihf/libqtelegram-ae.so.1
No symbol table info available.
#11 0xb3a6690e in ?? () from /opt/click.ubuntu.com/.click/users/@all/com.ubuntu.telegram/lib/arm-linux-gnueabihf/libqtelegram-ae.so.1
No symbol table info available.
#12 0xb5f15db4 in QMetaObject::activate(QObject*, int, int, void**) () from /usr/lib/arm-linux-gnueabihf/libQt5Core.so.5
No symbol table info available.
#13 0xb3a5fdb8 in Api::updatesDifference(long long, QList<Message> const&, QList<EncryptedMessage> const&, QList<Update> const&, QList<Chat> const&, QList<User> const&, UpdatesState const&) () from /opt/click.ubuntu.com/.click/users/@all/com.ubuntu.telegram/lib/arm-linux-gnueabihf/libqtelegram-ae.so.1
No symbol table info available.
#14 0xb3a36240 in Api::onUpdatesGetDifferenceAnswer(Query*, InboundPkt&) () from /opt/click.ubuntu.com/.click/users/@all/com.ubuntu.telegram/lib/arm-linux-gnueabihf/libqtelegram-ae.so.1
No symbol table info available.
#15 0xb3a49746 in AbstractApi::onResultReceived(Query*, InboundPkt&) () from /opt/click.ubuntu.com/.click/users/@all/com.ubuntu.telegram/...

At the moment I believe it´s not the encrypted chat making troubles but posting a link to the chat from Windows client, which resolved the preview image. Is the Touch client able to understand these previews correctly?

BR

Is this duplicate of 1512332 ??

Hi flohack, yes it is the duplicate of that one. But I appreciate the back trace!
I suspect it's a secret API layer 20 call that's crashing it, related to state of a secret chat.
I'm not sure when we get that fixed, though it has been escalated to critical.
I hate to suggest this, but if you need a workaround, and you do *NOT* care about loosing secret chats:
rm -rf .config/com.ubuntu.telegram
Otherwise, I'm bit clueless what I can recomment. We'll just have to get this fixed.

It is working again :)

Did you push smth in the latest OTA update? There was no real update of Telegram, or I am blind? Anyway, without deleting anything it works again.

BR