Fix custom thread name display issue

Fixes hishamhm#877

Author: jan-konczak-cs-put

Process.c

@@ -417,7 +417,7 @@ void Process_makeCommandStr(Process* this) {
       return;
    if (this->state == ZOMBIE && !this->mergedCommand.str)
       return;
-   if (Process_isUserlandThread(this) && settings->showThreadNames && (showThreadNames == mc->prevShowThreadNames))
+   if (Process_isUserlandThread(this) && settings->showThreadNames && (showThreadNames == mc->prevShowThreadNames) && (mc->prevMergeSet == showMergedCommand))
       return;
 
    /* this->mergedCommand.str needs updating only if its state or contents changed.
@@ -516,11 +516,14 @@ void Process_makeCommandStr(Process* this) {
    assert(cmdlineBasenameStart <= (int)strlen(cmdline));
 
    if (!showMergedCommand || !procExe || !procComm) { /* fall back to cmdline */
-      if (showMergedCommand && (!Process_isUserlandThread(this) || showThreadNames) && !procExe && procComm && strlen(procComm)) { /* Prefix column with comm */
+      if ((showMergedCommand || (Process_isUserlandThread(this) && showThreadNames)) && procComm && strlen(procComm)) { /* set column to or prefix it with comm */
          if (strncmp(cmdline + cmdlineBasenameStart, procComm, MINIMUM(TASK_COMM_LEN - 1, strlen(procComm))) != 0) {
             WRITE_HIGHLIGHT(0, strlen(procComm), commAttr, CMDLINE_HIGHLIGHT_FLAG_COMM);
             str = stpcpy(str, procComm);
 
+            if(!showMergedCommand)
+               return;
+
             WRITE_SEPARATOR;
          }
       }